Mozilla is a

free software Free software, libre software, libreware sometimes known as freedom-respecting software is computer software distributed open-source license, under terms that allow users to run the software for any purpose as well as to study, change, distribut ...

community founded in 1998 by members of

Netscape Netscape Communications Corporation (originally Mosaic Communications Corporation) was an American independent computer services company with headquarters in Mountain View, California, and then Dulles, Virginia. Its Netscape web browser was o ...

. The Mozilla community uses, develops, publishes and supports Mozilla products, thereby promoting free software and open standards. The community is supported institutionally by the

non-profit A nonprofit organization (NPO), also known as a nonbusiness entity, nonprofit institution, not-for-profit organization, or simply a nonprofit, is a non-governmental (private) legal entity organized and operated for a collective, public, or so ...

Mozilla Foundation The Mozilla Foundation is an American non-profit organization that exists to support and collectively lead the Open-source software, open source Mozilla project. Founded in July 2003, the organization sets the policies that govern development, ...

and its tax-paying subsidiary, the

Mozilla Corporation The Mozilla Corporation is a wholly owned subsidiary of the Mozilla Foundation that coordinates and integrates the development of Internet-related applications such as the Firefox web browser, by a global community of open-source developers, s ...

. Mozilla's current products include the

Firefox Mozilla Firefox, or simply Firefox, is a free and open-source web browser developed by the Mozilla Foundation and its subsidiary, the Mozilla Corporation. It uses the Gecko rendering engine to display web pages, which implements curr ...

web browser, Thunderbird e-mail client (now through a subsidiary), the

Bugzilla Bugzilla is a web-based general-purpose bug tracking system and testing tool originally developed and used by the Mozilla project, and licensed under the Mozilla Public License. Released as open-source software by Netscape Communications in 19 ...

bug tracking system, the

Gecko Geckos are small, mostly carnivorous lizards that have a wide distribution, found on every continent except Antarctica. Belonging to the infraorder Gekkota, geckos are found in warm climates. They range from . Geckos are unique among lizards ...

layout engine, and the

Pocket A pocket is a bag- or envelope-like receptacle either fastened to or inserted in an article of clothing to hold small items. Pockets are also attached to luggage, backpacks, and similar items. In older usage, a pocket was a separate small bag o ...

"read-it-later-online" service.

History

On January 23, 1998, Netscape announced that its

Netscape Communicator Netscape Communicator (or ''Netscape 4'') is a discontinued Internet suite produced by Netscape Communications Corporation, and was the fourth major release in the Netscape line of browsers. It was first in beta in 1996 and was released in Jun ...

browser software would be free, and that its source code would also be free. One day later,

Jamie Zawinski Jamie Werner Zawinski (born November 3, 1968), commonly known as jwz, is an American computer programmer, blogger, and impresario. He is best known for his role in the creation of Netscape Navigator, Netscape Mail, Lucid Emacs, Mozilla.org, an ...

of Netscape registered . The project took its name, "Mozilla", from the original code name of the

Netscape Navigator The 1990s releases of the Netscape (web browser), Netscape line referred to as Netscape Navigator were a series of now discontinued web browsers. from versions 1 to 4.08. It was the Core product, flagship product of the Netscape, Netscape Comm ...

browser—a

portmanteau In linguistics, a blend—also known as a blend word, lexical blend, or portmanteau—is a word formed by combining the meanings, and parts of the sounds, of two or more words together.

of "

Mosaic A mosaic () is a pattern or image made of small regular or irregular pieces of colored stone, glass or ceramic, held in place by plaster/Mortar (masonry), mortar, and covering a surface. Mosaics are often used as floor and wall decoration, and ...

and

Godzilla is a fictional monster, or ''kaiju'', that debuted in the eponymous 1954 film, directed and co-written by Ishirō Honda. The character has since become an international pop culture icon, appearing in various media: 33 Japanese films p ...

", and used to coordinate the development of the

Mozilla Application Suite The Mozilla Application Suite (originally known as Mozilla, marketed as the Mozilla Suite) is a discontinued cross-platform integrated Internet suite. Its development was initiated by Netscape Communications Corporation, before their acquisition ...

, the

version of Netscape's internet software,

. Zawinski said he arrived at the name "Mozilla" at a Netscape staff meeting. A small group of Netscape employees were tasked with coordinating the new community. Mozilla originally aimed to be a technology provider for companies such as Netscape, who would commercialize their

code. When Netscape's parent company AOL greatly reduced its involvement with Mozilla in July 2003, the

was designated the project's legal steward. Soon after, Mozilla deprecated the Mozilla Suite in favor of creating independent applications for each function, primarily the

web browser and the Thunderbird email client, and moved to supply them directly to the public. Mozilla's activities next expanded, and also experienced product terminations, with Firefox on mobile platforms (primarily Android), a mobile OS called

Firefox OS Firefox OS (project name: ''Boot to Gecko'', also known as ''B2G'') is a discontinued Open-source software, open-source operating system made for smartphones, tablet computers, smart TVs, and Matchstick TV, dongles designed by Mozilla and exte ...

(since cancelled), a web-based identity system called

Mozilla Persona Mozilla Persona was a decentralized authentication system for the web, based on the open BrowserID protocol prototyped by Mozilla and standardized by IETF. It was launched in July 2011, but after failing to achieve traction, Mozilla announced in ...

(since cancelled) and a marketplace for HTML5 applications. In a report released in November 2012, Mozilla reported that their revenue for 2011 was $163 million, up 33% from $123 million in 2010. It noted that roughly 85% of their revenue came from their contract with Google. Typeface Simple Zilla Slab

At the end of 2013, Mozilla announced a deal with

Cisco Cisco Systems, Inc. (using the trademark Cisco) is an American multinational digital communications technology conglomerate corporation headquartered in San Jose, California. Cisco develops, manufactures, and sells networking hardware, s ...

, whereby Firefox would download and use a Cisco-provided binary build of an open-source

codec A codec is a computer hardware or software component that encodes or decodes a data stream or signal. ''Codec'' is a portmanteau of coder/decoder. In electronic communications, an endec is a device that acts as both an encoder and a decoder o ...

to play the proprietary H.264 video format. As part of the deal, Cisco would pay any patent licensing fees associated with the binaries that it distributed. Mozilla's CTO,

Brendan Eich Brendan Eich ( ; born July 4, 1961) is an American computer programmer and technology executive. He created the JavaScript programming language and co-founded the Mozilla project, the Mozilla Foundation, and the Mozilla Corporation. He serve ...

, acknowledged that it was "not a complete solution" and wasn't "perfect". An employee in Mozilla's video formats team, writing unofficially, justified it by the need to maintain their large user base, which would be necessary for future battles for truly free video formats. In December 2013, Mozilla announced funding for the development of paid games through its Game Creator Challenge. However, even games that would be released under non-free or

licenses were required to be made with open web technologies and Javascript. In January 2017 the company rebranded away from its dinosaur symbol in favor of a logo including a "://" character sequence from a URL: "moz://a". As a part of the rebranding, it commissioned the

open source Open source is source code that is made freely available for possible modification and redistribution. Products include permission to use and view the source code, design documents, or content of the product. The open source model is a decentrali ...

slab serif In typography, a slab serif (also called ''mechanistic'', ''square serif'', ''antique'' or ''Egyptian'') typeface is a type of serif typeface characterized by thick, block-like serifs. Serif terminals may be either blunt and angular ( Rockwell), ...

font Zilla Slab. In 2020 Mozilla announced it would cut 25% of its worldwide staff of nearly 1,000 to reduce costs. Firefox has fallen from 30% market share to 4% in 10 years. Despite this, executive pay increased 400%, with Mitchell Baker, Mozilla’s top executive, receiving $2.4m in 2018. In December 2020, Mozilla closed its Mountain View office. Mozilla rebranded again in 2024 with a new "Reclaim the Internet" motto. The rebrand was assisted by Jones Knowles Ritchie.

Values

Seeking new products and roles while sustaining commitment to Firefox though Firefox's market share has so far dwindled dramatically, Executive Chairwoman and CEO Baker, Chief Product Officer Steve Teixeira and Mozilla Foundation Executive Director Mark Surman told Tech Crunch in November 2022 that fundamental business models are being rethought, and new roles in the internet as a human institution, that Mozilla's next 25 years' plan was in search of specifying projects for revised detailed purposes. The one actual general vehicle implemented "has meant the launch of Mozilla Ventures, a $35 million venture fund that the organization plans to use to invest in products and founders who want to build a better, privacy-respecting internet." Mozilla has used or promoted non-free resources in some circumstances, such as licensing the H.264 codec and promoting the development of paid games using open technologies.

Mozilla Manifesto

The Mozilla Manifesto outlines Mozilla's goals and principles. It asserts Mozilla's commitment to the

internet The Internet (or internet) is the Global network, global system of interconnected computer networks that uses the Internet protocol suite (TCP/IP) to communicate between networks and devices. It is a internetworking, network of networks ...

, saying: "The open, global internet is the most powerful communication and collaboration resource we have ever seen. It embodies some of our deepest hopes for human progress." It then outlines what Mozilla sees as its place in the development of the internet, stating "The Mozilla project uses a community-based approach to create world-class open source software and to develop new types of collaborative activities". And finally, it lays out their ten principles: # The internet is an integral part of modern life—a key component in education, communication, collaboration, business, entertainment, and society as a whole. # The internet is a global public resource that must remain open and accessible. # The internet must enrich the lives of individual human beings. # Individuals’ security and privacy on the internet are fundamental and must not be treated as optional. # Individuals must have the ability to shape the internet and their own experiences on it. # The effectiveness of the internet as a public resource depends upon interoperability (protocols, data formats, content), innovation, and decentralized participation worldwide. # Free and open source software promotes the development of the internet as a public resource. # Transparent community-based processes promote participation, accountability, and trust. # Commercial involvement in the development of the internet brings many benefits; a balance between commercial profit and public benefit is critical. # Magnifying the public benefit aspects of the internet is an important goal, worthy of time, attention, and commitment.

Pledge

According to the Mozilla Foundation:

Venture Incubation

Mozilla Builders

Throughout the 2020 year, Mozilla ran Mozilla Builders, "an experimental 'Fix-The-Internet' incubator program". It funded 80 projects through three subprograms: The Startup Studio, The MVP Lab and The Open Lab. The site for this program is now archived.

Mozilla Ventures

On November 2, 2022, at the Web Summit in Lisbon, Portugal and simultaneously online, Mozilla announced the early 2023 launch of Mozilla Ventures, a venture capital and product incubation facility out of Mozilla for independent start-ups, seed to Series A which qualify under the ethos of the Mozilla Manifesto, with a starting fund of $35 million. Its founding Managing Partner is Mohamed Nanabhay who told Entrepreneur India the purpose is "to create an ecosystem of entrepreneurs from across the world who are building companies that create a better internet". Mozilla Foundation President and Executive Director Mark Surman named the first 3 investment recipients in the Mozilla Ventures mode, in discussions before Mozilla Ventures was announced, as Secure AI Labs, Block Party and HeyLogin.

Software

Firefox

is a family of

software Software consists of computer programs that instruct the Execution (computing), execution of a computer. Software also includes design documents and specifications. The history of software is closely tied to the development of digital comput ...

products developed by Mozilla, with the Firefox browser as the flagship product.

Firefox browser

The

web browser A web browser, often shortened to browser, is an application for accessing websites. When a user requests a web page from a particular website, the browser retrieves its files from a web server and then displays the page on the user's scr ...

is available in both desktop and mobile versions. It uses the

layout engine to render web pages, which implements current and anticipated web standards. , Firefox had approximately 10–11% of worldwide

usage share of web browsers The usage share of web browsers is the portion, often expressed as a percentage, of visitors to a group of web sites that use a particular web browser. Accuracy Measuring browser usage in the number of requests (page hits) made by each user a ...

, making it the 4th most-used web browser. Firefox began as an experimental branch of the Mozilla codebase by Dave Hyatt, Joe Hewitt and Blake Ross, who believed the commercial requirements of

's sponsorship and developer-driven

feature creep Feature creep is the excessive ongoing expansion or addition of new features in a product, especially in computer software, video games (where it should not be confused with power creep) and consumer and business electronics. These extra feature ...

compromised the utility of the Mozilla browser. To combat what they saw as the Mozilla Suite's

software bloat Software bloat is a process whereby successive versions of a computer program become perceptibly slower, use more memory, disk space or processing power, or have higher hardware requirements than the previous version, while making only dubious ...

, they created a stand-alone browser, with which they intended to replace the Mozilla Suite. Firefox was originally named ''Phoenix'' but the name was changed to avoid trademark conflicts with

Phoenix Technologies Phoenix Technologies Ltd. is an American company that designs, develops and supports core system software for personal computers and other computing devices. The company's products commonly referred to as BIOS (Basic Input/Output System) or fir ...

. The initially-announced replacement, ''Firebird'', provoked objections from the Firebird project community. The current name, Firefox, was chosen on February 9, 2004. It was previously announced that Mozilla would launch a premium version of the Firefox browser by October 2019. The company's CEO, Chris Beard, was quoted by ''

The Next Web TNW (The Next Web) is a website and annual series of conferences focused on new technology and start-up companies in Europe. The Next Web company was established in 2006 by co-founders Boris Veldhuijzen van Zanten and Patrick de Laive in Amsterd ...

'': "there is no plan to charge money for things that are now free. So we will roll out a subscription service and offer a premium level." In September, Mozilla revealed their new offering, Firefox Premium Support, at $10 per installation. However, shortly after news broke of the service, Mozilla removed information about it from the website. Computerworld reported that in an email statement, Mozilla claimed "the page outlining that these paid support services for enterprise clients will be available was posted incorrectly." In October 2023, Mozilla announced that consumer 'Firefox accounts' were renamed to 'Mozilla accounts', explicitly indicating a desire to bring the Mozilla brand into greater prominence even with the diminution of some Firefox branding:

Over the years, Firefox accounts expanded its role beyond being solely an authentication solution for Firefox Sync. It now serves as Mozilla's main authentication and account management service for a wide range of products and services, supporting millions of active account customers globally. As such, the original “Firefox” branding no longer accurately reflects the broad scope of Mozilla's offerings. The renaming is intended to create a more consistent brand experience across all Mozilla surfaces, driving higher awareness of the portfolio of Mozilla products.

Firefox for mobile

Firefox for mobile (codenamed ''Fennec'') is the build of the

Mozilla Firefox Mozilla Firefox, or simply Firefox, is a free and open-source web browser developed by the Mozilla Foundation and its subsidiary, the Mozilla Corporation. It uses the Gecko rendering engine to display web pages, which implements curren ...

for mobile devices such as

smartphone A smartphone is a mobile phone with advanced computing capabilities. It typically has a touchscreen interface, allowing users to access a wide range of applications and services, such as web browsing, email, and social media, as well as multi ...

s and

tablet computer A tablet computer, commonly shortened to tablet, is a mobile device, typically with a mobile operating system and touchscreen display processing circuitry, and a rechargeable battery in a single, thin and flat package. Tablets, being computers ...

s. Initially available on multiple platforms, it is now available in two versions: Firefox for Android and Firefox for iOS. Firefox for Android runs on the Android

mobile operating system A mobile operating system is an operating system used for smartphones, tablets, smartwatches, smartglasses, or other non-laptop personal mobile computing devices. While computers such as laptops are "mobile", the operating systems used on the ...

and uses the same

layout engine as

; for example, version 1.0 used the same engine as Firefox 3.6, and the following release, 4.0, shared core code with Firefox 4.0. Firefox for iOS, which runs on the

iOS Ios, Io or Nio (, ; ; locally Nios, Νιός) is a Greek island in the Cyclades group in the Aegean Sea. Ios is a hilly island with cliffs down to the sea on most sides. It is situated halfway between Naxos and Santorini. It is about long an ...

mobile operating system, does not use the Gecko Layout Engine because of

Apple An apple is a round, edible fruit produced by an apple tree (''Malus'' spp.). Fruit trees of the orchard or domestic apple (''Malus domestica''), the most widely grown in the genus, are agriculture, cultivated worldwide. The tree originated ...

's policy that all iOS apps that browse the web must use the built-in iOS

WebKit WebKit is a browser engine primarily used in Apple's Safari web browser, as well as all web browsers on iOS and iPadOS. WebKit is also used by the PlayStation consoles starting with the PS3, the Tizen mobile operating systems, the Amazon K ...

rendering engine. Both version include features like

HTML5 HTML5 (Hypertext Markup Language 5) is a markup language used for structuring and presenting hypertext documents on the World Wide Web. It was the fifth and final major HTML version that is now a retired World Wide Web Consortium (W3C) recommend ...

support, Firefox Sync,

private browsing Private browsing (also known as incognito mode or private mode) is a feature in most web browsers that enhances user privacy. In this mode, the browser initiates a temporary session separate from its main session and user data. The browsing ...

web tracking Web tracking is the practice by which operators of websites and third parties collect, store and share information about visitors' activities on the World Wide Web. Analysis of a user's behaviour may be used to provide content that enables the op ...

protection, and

tabbed browsing In interface design, a tab is a graphical user interface object that allows multiple documents or Panel (computer software), panels to be contained within a single window (computing), window, using tabs as a navigational widget for switching be ...

, and Firefox for Android also includes support for add-ons.

Firefox Focus

Firefox Focus is a free and open-source privacy-focused

mobile browser A mobile browser is a web browser designed for use on a mobile device such as a mobile phone, PDA, smartphone, or tablet. Mobile browsers are optimized to display web content most effectively on small screens on portable devices. Some mobile bro ...

for Android and

. Initially released in 2015 as only a tracker-blocking application for iOS, it has since been developed into a full mobile browser for both iOS and Android.

Firefox Lockwise

Firefox Lockwise was a

password manager A password manager is a software program to prevent password fatigue by Random password generator, automatically generating, Autofill, autofilling and storing Password, passwords. It can do this for Application software, local applications or web ...

offered by Mozilla. On desktop, it was a built-in feature of the

browser. On mobile, it was offered as a standalone app that could be set as the device's default password manager.

Firefox Monitor

Firefox Monitor is an online service that informs users if their

email address An email address identifies an email box to which messages are delivered. While early messaging systems used a variety of formats for addressing, today, email addresses follow a set of specific rules originally standardized by the Internet Enginee ...

and

password A password, sometimes called a passcode, is secret data, typically a string of characters, usually used to confirm a user's identity. Traditionally, passwords were expected to be memorized, but the large number of password-protected services t ...

s have been leaked in

data breach A data breach, also known as data leakage, is "the unauthorized exposure, disclosure, or loss of personal information". Attackers have a variety of motives, from financial gain to political activism, political repression, and espionage. There ...

es.

Firefox Send

Firefox Send was an online encrypted file-transfer service offered by Mozilla. In September 2020, Mozilla announced that it would be decommissioned and would no longer be part of the product lineup.

Solo AI Website Creator

Solo is a free AI

website builder Website builders are tools that typically allow the construction of websites without manual code editing. They fall into two categories: * Online proprietary tools provided by web hosting service companies. These are typically intended for serv ...

for solopreneurs.

Mozilla VPN

Mozilla VPN, formerly Firefox Private Network, is a subscription-based VPN and a free privacy extension.

A-Frame

Mozilla developed A-Frame, an open-source web framework designed to simplify the creation of

virtual reality Virtual reality (VR) is a Simulation, simulated experience that employs 3D near-eye displays and pose tracking to give the user an immersive feel of a virtual world. Applications of virtual reality include entertainment (particularly video gam ...

(VR) and 3D experiences in web browsers. Released in 2015, A-Frame is built on top of

WebGL WebGL (short for Web Graphics Library) is a JavaScript Application programming interface, API for rendering interactive 2D and 3D graphics within any compatible web browser without the use of plug-in (computing), plug-ins. WebGL is fully integra ...

and uses

HTML Hypertext Markup Language (HTML) is the standard markup language for documents designed to be displayed in a web browser. It defines the content and structure of web content. It is often assisted by technologies such as Cascading Style Sheets ( ...

-like syntax, making it accessible to web developers without requiring deep knowledge of complex 3D programming. A-Frame enables users to build immersive VR experiences that are compatible with a wide range of devices, from desktop browsers to mobile VR headsets like Oculus Rift and Google Cardboard. It also integrates with other popular web technologies, such as Three.js, to provide advanced capabilities for developers. As part of Mozilla’s broader efforts in promoting the immersive web and WebXR (a standard for virtual and augmented reality experiences on the web), A-Frame has contributed to the democratization of VR development. It allows creators to develop and share VR content that is accessible directly through a web browser, removing the need for specialized software or apps. A-Frame has since grown into a widely-used framework in the web development and VR communities, with contributions from developers around the world. Mozilla continues to support the project as part of its commitment to an open and immersive web.

Firefox Private Relay

Firefox Private Relay provides users with

disposable email address Disposable email addressing, also known as DEA, dark mail or masked email, refers to an approach that involves using a unique email address for each contact or entity, or using it for a limited number of times or uses. The benefit is that if the e ...

es that can be used to combat spam (by hiding the user's real email address) and manage email subscriptions by categorizing them based on the party a particular address was given to. Firefox Relay was first released as a Firefox add-on on April 9, 2020. Mozilla announced Firefox Relay Premium monthly subscription service, ending

Beta version The software release life cycle is the process of developing, testing, and distributing a software product (e.g., an operating system). It typically consists of several stages, such as pre-alpha, alpha, beta, and release candidate, before the fi ...

of Firefox Relay on November 19, 2021. In addition to this, users who benefit from the subscription can receive unlimited alias emails as [email protected] as @relay.firefox.com Instead of the pseudonymous e-mail addresses provided, @mozmail.com e-mail addresses have been switched.

Firefox Reality

In September 2018, Mozilla announced that its VR version was ready for consumers to download. Called Firefox Reality, the browser was built entirely for virtual reality. It is currently available on the Oculus. In January 2019, HTC announced its partnership with Mozilla, under which the Firefox Reality web browser has been made available on Vive headsets. In February 2022, Mozilla announced that

Igalia Igalia is a private, worker-owned, employee-run cooperative model consultancy focused on open source software. Based in A Coruña, Galicia_(Spain), Galicia (Spain), Igalia is known for its contributions and commitments to both open-source and ope ...

had assumed stewardship of the project, whose name was changed to Wolvic. Mozilla does not support Firefox Reality anymore.

Firefox OS

Firefox OS (project name: ''Boot to Gecko'' also known as ''B2G'') is a

operating system An operating system (OS) is system software that manages computer hardware and software resources, and provides common daemon (computing), services for computer programs. Time-sharing operating systems scheduler (computing), schedule tasks for ...

developed by Mozilla to support

apps written using " open Web" technologies rather than platform-specific native

API An application programming interface (API) is a connection between computers or between computer programs. It is a type of software interface, offering a service to other pieces of software. A document or standard that describes how to build ...

s. The concept behind Firefox OS is that all user-accessible software will be HTML5 applications, using Open Web APIs to access the phone's hardware directly via

JavaScript JavaScript (), often abbreviated as JS, is a programming language and core technology of the World Wide Web, alongside HTML and CSS. Ninety-nine percent of websites use JavaScript on the client side for webpage behavior. Web browsers have ...

. Some devices using the OS include Alcatel One Touch Fire, ZTE Open, and LG Fireweb. Mozilla announced the end of Firefox OS development in December 2015. A fork of B2G,

KaiOS KaiOS is a mobile Linux distribution for keypad-based mobile phones. It is designed and optimised for affordable and low-power feature phones, while retaining access to Internet services through web apps, based on the Gecko engine. KaiOS was ...

, has continued development and ships with numerous low-cost devices.

Pocket

is a

mobile application A mobile application or app is a computer program or software application designed to run on a mobile device such as a phone, tablet, or watch. Mobile applications often stand in contrast to desktop applications which are designed to run on d ...

and

web service A web service (WS) is either: * a service offered by an electronic device to another electronic device, communicating with each other via the Internet, or * a server running on a computer device, listening for requests at a particular port over a n ...

for managing a reading list of articles from the Internet. It was announced that it would be acquired by the

, the commercial arm of Mozilla's

development group, on February 27, 2017. Originally designed only for desktop browsers, it is now available for

macOS macOS, previously OS X and originally Mac OS X, is a Unix, Unix-based operating system developed and marketed by Apple Inc., Apple since 2001. It is the current operating system for Apple's Mac (computer), Mac computers. With ...

Windows Windows is a Product lining, product line of Proprietary software, proprietary graphical user interface, graphical operating systems developed and marketed by Microsoft. It is grouped into families and subfamilies that cater to particular sec ...

, Android,

Windows Phone Windows Phone (WP) is a discontinued mobile operating system developed by Microsoft Mobile for smartphones as the replacement successor to Windows Mobile and Zune. Windows Phone featured a new user interface derived from the Metro design languag ...

BlackBerry BlackBerry is a discontinued brand of handheld devices and related mobile services, originally developed and maintained by the Canadian company Research In Motion (RIM, later known as BlackBerry Limited) until 2016. The first BlackBerry device ...

, Kobo eReaders, and

Thunderbird

Thunderbird is a

, cross-platform email and news client developed by the volunteers of the Mozilla Community. On July 16, 2012, Mitchell Baker announced that Mozilla's leadership had come to the conclusion that ongoing stability was the most important thing for Thunderbird and that innovation in Thunderbird was no longer a priority for Mozilla. In that update, Baker also suggested that Mozilla had provided a pathway for its community to innovate around Thunderbird if the community chooses. On July 11, 2023, the Thunderbird blog announced the release of a new version of Thunderbird called Supernova. It features a new, modernized, user interface, among other new features. Changes have also been made to the older underlying code structure to make "maintenance and extensibility easier".

SeaMonkey

SeaMonkey SeaMonkey is a free and open-source Internet suite. It is the continuation of the former Mozilla Application Suite, based on the same source code, which itself grew out of Netscape Communicator and formed the base of Netscape 6 and Netscape ...

(formerly the Mozilla Application Suite) is a free and open-source cross-platform suite of Internet software components including a web browser component, a client for sending and receiving email and

Usenet Usenet (), a portmanteau of User's Network, is a worldwide distributed discussion system available on computers. It was developed from the general-purpose UUCP, Unix-to-Unix Copy (UUCP) dial-up network architecture. Tom Truscott and Jim Elli ...

newsgroup messages, an HTML editor ( Mozilla Composer) and the ChatZilla IRC client. On March 10, 2005, the

announced that it would not release any official versions of Mozilla Application Suite beyond 1.7.x, since it had now focused on the stand-alone applications

and Thunderbird. SeaMonkey is now maintained by the SeaMonkey Council, which has

trademark A trademark (also written trade mark or trade-mark) is a form of intellectual property that consists of a word, phrase, symbol, design, or a combination that identifies a Good (economics and accounting), product or Service (economics), service f ...

ed the SeaMonkey name with help from the Mozilla Foundation. The Mozilla Foundation provides project hosting for the SeaMonkey developers.

Bugzilla

is a

web Web most often refers to: * Spider web, a silken structure created by the animal * World Wide Web or the Web, an Internet-based hypertext system Web, WEB, or the Web may also refer to: Computing * WEB, a literate programming system created by ...

-based general-purpose

bug tracking system Tracking system or defect tracking system is a software application that keeps track of reported software bugs in software development projects. It may be regarded as a type of issue tracking system. Many bug tracking systems, such as those used ...

, which was released as

Netscape Communications Netscape Communications Corporation (originally Mosaic Communications Corporation) was an American independent computer services company with headquarters in Mountain View, California, and then Dulles, Virginia. Its Netscape (web browser), Nets ...

in 1998 along with the rest of the Mozilla codebase, and is currently stewarded by Mozilla. It has been adopted by a variety of organizations for use as a

for both

free and open-source software Free and open-source software (FOSS) is software available under a license that grants users the right to use, modify, and distribute the software modified or not to everyone free of charge. FOSS is an inclusive umbrella term encompassing free ...

and proprietary projects and products, including the

, the

Linux kernel The Linux kernel is a Free and open-source software, free and open source Unix-like kernel (operating system), kernel that is used in many computer systems worldwide. The kernel was created by Linus Torvalds in 1991 and was soon adopted as the k ...

KDE KDE is an international free software community that develops free and open-source software. As a central development hub, it provides tools and resources that enable collaborative work on its projects. Its products include the KDE Plasma gra ...

Red Hat Red Hat, Inc. (formerly Red Hat Software, Inc.) is an American software company that provides open source software products to enterprises and is a subsidiary of IBM. Founded in 1993, Red Hat has its corporate headquarters in Raleigh, North ...

Eclipse An eclipse is an astronomical event which occurs when an astronomical object or spacecraft is temporarily obscured, by passing into the shadow of another body or by having another body pass between it and the viewer. This alignment of three ...

and

LibreOffice LibreOffice () is a free and open-source office productivity software suite developed by The Document Foundation (TDF). It was created in 2010 as a fork of OpenOffice.org, itself a successor to StarOffice. The suite includes applications ...

WebThings

WebThings is a framework that allowed management of IoT devices through a single framework, gateway and UI. It was based on W3C

Web of Things Web most often refers to: * Spider web, a silken structure created by the animal * World Wide Web or the Web, an Internet-based hypertext system Web, WEB, or the Web may also refer to: Computing * WEB, a literate programming system created by ...

standard. Since 2020, it is no longer affiliated with Mozilla. It was spun off as an independent project following layoffs in 2020. It was known as ''Project Things'' and allowed users to use a

Raspberry Pi Raspberry Pi ( ) is a series of small single-board computers (SBCs) developed in the United Kingdom by the Raspberry Pi Foundation in collaboration with Broadcom Inc., Broadcom. To commercialize the product and support its growing demand, the ...

as a gateway for IoT management with decentralized software.

Components

NSS

Network Security Services (NSS) comprises a set of

libraries A library is a collection of Book, books, and possibly other Document, materials and Media (communication), media, that is accessible for use by its members and members of allied institutions. Libraries provide physical (hard copies) or electron ...

designed to support

cross-platform Within computing, cross-platform software (also called multi-platform software, platform-agnostic software, or platform-independent software) is computer software that is designed to work in several Computing platform, computing platforms. Some ...

development of security-enabled client and server applications. NSS provides a complete

implementation of crypto libraries supporting SSL and S/MIME. NSS is licensed under the GPL-compatible

Mozilla Public License The Mozilla Public License (MPL) is a free and open-source weak copyleft license for most Mozilla Foundation software such as Firefox and Thunderbird. The MPL is developed and maintained by Mozilla, which seeks to balance the concerns of bo ...

2.0. AOL,

Sun Microsystems Sun Microsystems, Inc., often known as Sun for short, was an American technology company that existed from 1982 to 2010 which developed and sold computers, computer components, software, and information technology services. Sun contributed sig ...

Oracle Corporation Oracle Corporation is an American Multinational corporation, multinational computer technology company headquartered in Austin, Texas. Co-founded in 1977 in Santa Clara, California, by Larry Ellison, who remains executive chairman, Oracle was ...

Google Google LLC (, ) is an American multinational corporation and technology company focusing on online advertising, search engine technology, cloud computing, computer software, quantum computing, e-commerce, consumer electronics, and artificial ...

and other companies and individual contributors have co-developed NSS and it is used in a wide range of non-Mozilla products including

Evolution Evolution is the change in the heritable Phenotypic trait, characteristics of biological populations over successive generations. It occurs when evolutionary processes such as natural selection and genetic drift act on genetic variation, re ...

Pidgin A pidgin , or pidgin language, is a grammatically simplified form of contact language that develops between two or more groups of people that do not have a language in common: typically, its vocabulary and grammar are limited and often drawn f ...

, and

SpiderMonkey

SpiderMonkey SpiderMonkey is an open-source JavaScript and WebAssembly engine by the Mozilla Foundation. The engine powers the Firefox Web browser and has used multiple generations of JavaScript just-in-time (JIT) compilers, including TraceMonkey, Jäg ...

is the original

JavaScript engine The first engines for JavaScript were mere interpreters of the source code, but all relevant modern engines use just-in-time compilation for improved performance. JavaScript engines are typically developed by web browser vendors, and every maj ...

developed by

when he invented

in 1995 as a developer at

. It became part of the Mozilla product family when Mozilla inherited Netscape's code-base in 1998. In 2011, Eich transferred the nominal ownership of the SpiderMonkey code and project to Dave Mandelin. SpiderMonkey is a

engine written in C++ which implements

ECMAScript ECMAScript (; ES) is a standard for scripting languages, including JavaScript, JScript, and ActionScript. It is best known as a JavaScript standard intended to ensure the interoperability of web pages across different web browsers. It is stan ...

, a standard developed from JavaScript. It comprises an

interpreter Interpreting is translation from a spoken or signed language into another language, usually in real time to facilitate live communication. It is distinguished from the translation of a written text, which can be more deliberative and make use o ...

, several just-in-time compilers, a

decompiler A decompiler is a computer program that translates an executable file back into high-level source code. Unlike a compiler, which converts high-level code into machine code, a decompiler performs the reverse process. While disassemblers translate e ...

and a garbage collector. Products which embed SpiderMonkey include

, Thunderbird,

, and many non-Mozilla applications.

Rhino

Rhino is a

managed by the

. Developed entirely in

Java Java is one of the Greater Sunda Islands in Indonesia. It is bordered by the Indian Ocean to the south and the Java Sea (a part of Pacific Ocean) to the north. With a population of 156.9 million people (including Madura) in mid 2024, proje ...

, it converts JavaScript scripts into Java classes. It works in both compiled and interpreted mode.

Gecko

is a layout engine that supports web pages written using

, SVG, and

MathML Mathematical Markup Language (MathML) is a pair of mathematical markup languages, an application of XML for describing mathematical notations and capturing both its structure and content. Its aim is to natively integrate mathematical formulae ...

. Written in C++, it uses NSPR for platform independence. Its source code is licensed under the

. Firefox uses Gecko for rendering web pages and for rendering its

user interface In the industrial design field of human–computer interaction, a user interface (UI) is the space where interactions between humans and machines occur. The goal of this interaction is to allow effective operation and control of the machine fro ...

. Gecko is also used by Thunderbird, SeaMonkey, and many non-Mozilla applications.

Rust

Rust Rust is an iron oxide, a usually reddish-brown oxide formed by the reaction of iron and oxygen in the catalytic presence of water or air moisture. Rust consists of hydrous iron(III) oxides (Fe2O3·nH2O) and iron(III) oxide-hydroxide (FeO(OH) ...

is a compiled

programming language A programming language is a system of notation for writing computer programs. Programming languages are described in terms of their Syntax (programming languages), syntax (form) and semantics (computer science), semantics (meaning), usually def ...

developed by Mozilla Research. It is designed for safety, concurrency and performance. It is intended for creating large, complex software which must be both fast and safe against exploits. Rust is being used in an experimental layout engine, Servo, which was developed by Mozilla and Samsung. Although Servo is not yet used in any consumer-oriented browsers, the project developers plan for parts of its source code to be incrementally merged into Gecko and Firefox.

XULRunner

XULRunner XULRunner is a discontinued, packaged version of the Mozilla platform to enable standalone desktop application development using XUL, developed by Mozilla. It replaced the ''Gecko Runtime Environment'', a stalled project with a similar purpose. ...

is a software platform and technology experiment by Mozilla that allows applications built with the same technologies used by Firefox extensions (XPCOM, Javascript, HTML, CSS, XUL) to be run natively as desktop applications, without requiring Firefox to be installed. XULRunner binaries are available for the Windows, Linux and OS X operating systems, allowing such applications to be effectively cross-platform.

pdf.js

Pdf.js is a library developed by Mozilla that allows in-browser rendering of PDF documents using HTML5 Canvas and JavaScript. It is included by default in Firefox and Thunderbird, allowing the browser to render and edit PDF documents without requiring an external plugin. It is available separately as an extension, "PDF Viewer", for Firefox for Android, SeaMonkey, and the Firefox versions which don't include it built-in. It can also be included as part of a website's scripts, to allow PDF rendering for any browser that implements the required HTML5 features and can run JavaScript.

Sccache

sccache is a compiler caching tool, written in

similar to Ccache. It acts as a compiler wrapper to avoid unnecessary compilation, storing cached results on local disks or various cloud storage backends. sccache supports caching for C/ C++C/ code,

, and NVIDIA's

CUDA In computing, CUDA (Compute Unified Device Architecture) is a proprietary parallel computing platform and application programming interface (API) that allows software to use certain types of graphics processing units (GPUs) for accelerated gene ...

using NVCC (compiler).

Shumway

Shumway is a

replacement for

Adobe Flash Player Adobe Flash Player (known in Internet Explorer, Firefox, and Google Chrome as Shockwave Flash) is a discontinuedExcept in China, where it continues to be used, as well as Harman for enterprise users. computer program for viewing multimedia ...

developed by Mozilla since 2012, using open web technologies as a replacement for Flash technologies. It uses Javascript and HTML5 Canvas elements to render Flash and execute Actionscript. It is included by default in Firefox Nightly and can be installed as an extension for any recent version of Firefox. The last implementation was limited in its capabilities to render Flash content outside simple projects. The project was cancelled in 2016.

Servo

Servo is a browser engine being developed for application and embedded use. In August 2020, during the

COVID-19 pandemic The COVID-19 pandemic (also known as the coronavirus pandemic and COVID pandemic), caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), began with an disease outbreak, outbreak of COVID-19 in Wuhan, China, in December ...

, due to lack of funds and organization restructuring, Mozilla laid off most of the Servo development team. Servo then became part of the

Linux Foundation The Linux Foundation (LF) is a non-profit organization established in 2000 to support Linux development and open-source software projects. Background The Linux Foundation started as Open Source Development Labs in 2000 to standardize and prom ...

, where development currently continues.

SOPS: Secrets OPerationS

SOPS is an editor of encrypted files that supports YAML, JSON, ENV, INI and BINARY formats and encrypts with AWS KMS, GCP KMS, Azure Key Vault, age, and PGP.

Taskcluster

Taskcluster is a task execution framework supporting Mozilla's continuous integration and release processes. Initially designed for Firefox's automated builds and tests, it's a flexible, scalable open-source framework. Taskcluster is used extensively for building and releasing

, Thunderbird, NSS and other Mozilla projects.

WebXR Viewer

WebXR Viewer is an AR viewer that lets developers create and run AR experiences built with web technologies and ARKit.

Other activities

Mozilla VR

Mozilla VR is a team focused on bringing tools, specifications, and standards to the open Web. Mozilla VR maintains, a web framework for building VR experiences, and works on advancing WebVR support within web browsers. On April 26, 2018, the first experiment from their Social Mixed Reality efforts was released
Hubs
a multi-user virtual space in WebVR. Following Mozilla's restructuring in 2024, the company ceased operations for its virtual reality initiative, including Mozilla Hubs, as of May 31, 2024.

Mozilla Persona

was a secure, cross-browser website

authentication Authentication (from ''authentikos'', "real, genuine", from αὐθέντης ''authentes'', "author") is the act of proving an Logical assertion, assertion, such as the Digital identity, identity of a computer system user. In contrast with iden ...

mechanism which allowed a user to use a single username and password (or other authentication method) to log into multiple sites. Mozilla Persona shut down on November 30, 2016.

Mozilla Location Service

This

crowdsourced geolocation service was started by Mozilla in 2013 and offers a free

. In March 2024, it was announced that MLS would be retired and that functionality will be reduced in stages until the project is archived in July.

Webmaker

Mozilla Webmaker is Mozilla's educational initiative, and Webmaker's goal is to "help millions of people move from using the web to making the web." As part of Mozilla's non-profit mission, Webmaker aims "to help the world increase their understanding of the web, take greater control of their online lives, and create a more web literate planet."

MDN Web Docs

Mozilla maintains a comprehensive developer documentation website called the

MDN Web Docs MDN Web Docs, previously Mozilla Developer Network and formerly Mozilla Developer Center, is a documentation repository and learning resource for web developers. It was started by Mozilla in 2005 as a unified place for documentation about open ...

which contains information about web technologies including

, CSS, SVG,

, as well as Mozilla-specific information. In addition, Mozilla publishes a large number of videos about web technologies and the development of Mozilla projects on the Air Mozilla website. This was renamed to MDN Plus.

Common Voice

In July 2017, Mozilla launched the project Common Voice to help make voice recognition open to everyone. Visitors to the website can donate their voice to help build a

voice recognition engine that anyone can use to make apps for devices and the web that make use of voice recognition. The website allows visitors to read a sentence to help the machine system learn how real people speak, as well as validate the read sentences of other people. Mozilla publishes Common Voice data sets under a CC-0 license.

IRL – Online Life Is Real Life

On June 26, 2017, Mozilla launched ''IRL – Online Life Is Real Life'' to explore popular stories from the web that deal with issues of the internet that affect society as a whole.

Controversies

Directory tiles

In February 2014, Mozilla released Directory Tiles, which showed Firefox users advertisements based on the users browser history, which was opt-in by default. This feature was controversial, and prompted Mozilla to cancel the feature in December 2015.

Looking Glass Add-on

On December 15, 2017, Mozilla installed an add-on in all Firefox Quantum browsers, titled "Looking Glass," with the description, “MY REALITY IS JUST DIFFERENT THAN YOURS,” after a collaboration of Mozilla and the television show

Mr. Robot ''Mr. Robot'' is an American drama thriller television series created by Sam Esmail for USA Network. It stars Rami Malek as Elliot Alderson, a cybersecurity engineer and hacker with social anxiety disorder, clinical depression, and dissoci ...

. Mozilla received some criticism, as the add-on was installed without the user's knowledge or consent. On December 18, Mozilla issued an apology for the installation of the extension, and released the source code of the add-on.

Cliqz search engine

In October 2017, Mozilla launched an experimental add-on using Cliqz technology to "less than one percent of users in Germany installing Firefox." Cliqz recommended results based on the user's browser history, which drew criticism from users.

Push Notifications for Mozilla Blog without user consent

In July 2020 Mozilla forced push notifications, an advertisement for its own blog post about Facebook and Mozilla's ''#StopHateForProfit'' campaign. These notifications were sent without user consent and faced a backlash by Firefox users.

Federal labor charges

In January 2025, Mozilla settled charges from the

National Labor Relations Board The National Labor Relations Board (NLRB) is an Independent agencies of the United States government, independent agency of the federal government of the United States that enforces United States labor law, U.S. labor law in relation to collect ...

that the company had refused to hire #AppleToo activist and software engineer Cher Scarlett for her prior labor advocacy in 2021. They agreed to pay $300,000 in lost benefits and wages and to post a notification of rights, a promise not retaliate, and of the settlement to employees. The charge was filed by Scarlett in 2022 and prosecuted in 2023.

Mozilla Monitor - OneRep Partnership

Mozilla Monitor partners with OneRep to issue data removal requests from online directories and data aggregators. On March 14, 2024, an investigation by Krebs on Security revealed that OneRep's founder had also founded multiple people-search companies in the past. In response, Mozilla responded in a statement to Krebs on Security "We were aware of the past affiliations with the entities named in the article and were assured they had ended prior to our work together. We’re now looking into this further. We will always put the privacy and security of our customers first and will provide updates as needed.” Following up on their statement shortly after, Mozilla's vice president of communications told

The Verge ''The Verge'' is an American Technology journalism, technology news website headquarters, headquartered in Lower Manhattan, New York City and operated by Vox Media. The website publishes news, feature stories, guidebooks, product reviews, cons ...

that it had ended the partnership with OneRep. In February 2025, Krebs on Security found that Mozilla was still using and promoting OneRep.

Discrimination lawsuit

In June 2024, Steve Teixeira, who was the CPO of Mozilla Corporation, filed a lawsuit against the company. Teixeira alleges that he faced discrimination and retaliation by Mozilla after taking three months off to receive cancer treatment, and that "immediately upon his return, Mozilla campaigned to demote or terminate Mr. Teixeira citing groundless concerns and assumptions about his capabilities as an individual living with cancer."

NOYB complaint

In September 2024, NOYB filed a complaint with the Austrian data protection authority against Mozilla after enabling an experimental feature called "Privacy Preserving Attribution" in Firefox. The feature, designed to "allow ad performance to be measured without individual websites collecting personal data" was accused of tracking users without consent and infringing on the

GDPR The General Data Protection Regulation (Regulation (EU) 2016/679), abbreviated GDPR, is a European Union regulation on information privacy in the European Union (EU) and the European Economic Area (EEA). The GDPR is an important component of ...

Terms of Use and Privacy Policy changes

In 2025, Mozilla received criticism after changes to the Firefox Terms of Use. The criticism was centered around a clause that gave Mozilla a "nonexclusive, royalty-free, worldwide license" to use any information that was uploaded or inputted into the browser. The new terms were perceived to reduce privacy, and was seen to be connected to AI, while Mozilla denied that these were the motives. Criticism centered on fears that the license grant covered all data inputted, while Mozilla responded saying that the change "does NOT give us ownership of your data". In an attempt to respond to the fallout, Mozilla said that many modified words were to ease readability, increase transparency, formalize existing implicit agreements, and describe the circumstances of a free browser, adding that the AI features are covered by a separate agreement. Days later, Mozilla changed the wording of their privacy FAQ, removing a pledge to never "sell your personal data" and revising another section denying allegations that it sold user data, saying that it gathers some information from hideable advertisements as well as chatbot metadata when interacted with, and that the legal definition of "sell" was vague in some jurisdictions.

Community

The Mozilla Community consists of over 40,000 active contributors from across the globe. It includes both paid employees and volunteers who work towards the goals set forth in the Mozilla Manifesto. Many of the sub-communities in Mozilla have formed around localization efforts for Mozilla Firefox, and the Mozilla web properties.

Local communities

There are a number of sub-communities that exist based on their geographical locations, where contributors near each other work together on particular activities, such as localization, marketing, PR, and user support. In 2017, Mozilla created a Wireless Innovation for Network Security (WINS) challenge that awarded a total of $2 million in prize money to innovators who used its decentralized design to create wireless solutions for post-natural disaster internet access. This challenge also envisioned connecting communities that lacked internet access.

Mozilla Reps

The Mozilla Reps program was a volunteer-based program, which allowed volunteers to become official representatives of Mozilla. Volunteers were required to be 18 years or older in order to participate in the program. Activities under the program included recruitment for contributors, workshops, and attending Mozilla summits. The initiative ended in 2023.

Conferences and events

Mozilla Festival

The Mozilla Festival (MozFest) is a unique hybrid: part art, tech, and society convening, part maker festival, and the premiere gathering for activists in diverse global movements fighting for a more humane digital world. Journalists, coders, filmmakers, designers, educators, gamers, makers, youth, and anyone else, from all over the world, are encouraged to attend, with nearly 10,000 participating virtually in 2021 from more than 87 countries, working together at the intersection of human rights,

climate justice Climate justice is a type of environmental justice that focuses on the unequal impacts of climate change on marginalized or otherwise vulnerable populations. Climate justice seeks to achieve an equitable distribution of both the burdens of clima ...

, and technology, specifically trustworthy artificial intelligence. The event revolves around key issues based on the chosen theme for that year's festival. MozFest unfolds over the span of two weeks, with more than 500 interactive sessions, films, talks, round-tables, hack-a-thons, exhibits, and socials. Topics range from privacy best practices, developing solutions to online misinformation and harassment, building

tools, supporting Trustworthy AI innovations, and more. The titles of the festival revolve around the main theme, freedom, and the Web.

MozCamps

MozCamps are multi-day gatherings aimed at growing the contributor network by providing lectures, workshops, and breakout sessions led by Mozilla staff and volunteers. While these camps have been held in multiple locations globally in the past, none have occurred .

Mozilla Summit

Mozilla Summit was a global event with active contributors and Mozilla employees who collaborated to develop a shared understanding of Mozilla's mission together. Over 2,000 people representing 90 countries and 114 languages gathered in Santa Clara, Toronto, and Brussels in 2013. Mozilla had its last Summit in 2017 and replaced them with smaller All Hands gatherings, where both employees and volunteers come together to collaborate.

References

External links

*, includin
the Mozilla Manifesto
* Mozilla Wiki * /hg.mozilla.org/ Mozilla Mercurial Repository {{Authority control 1998 establishments in the United States Netscape Projects established in 1998