|
Robots.txt
The robots exclusion standard, also known as the robots exclusion protocol or simply robots.txt, is a standard used by websites to indicate to visiting web crawlers and other web robots which portions of the site they are allowed to visit. This relies on voluntary compliance. Not all robots comply with the standard; email harvesters, spambots, malware and robots that scan for security vulnerabilities may even start with the portions of the website where they have been told to stay out. The "robots.txt" file can be used in conjunction with sitemaps, another robot inclusion standard for websites. History The standard was proposed by Martijn Koster, when working for Nexor in February 1994 on the ''www-talk'' mailing list, the main communication channel for WWW-related activities at the time. Charles Stross claims to have provoked Koster to suggest robots.txt, after he wrote a badly-behaved web crawler that inadvertently caused a denial-of-service attack on Koster's server. It ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Sitemaps
The Sitemaps protocol allows a webmaster to inform search engines about URLs on a website that are available for crawling. A Sitemap is an XML file that lists the URLs for a site. It allows webmasters to include additional information about each URL: when it was last updated, how often it changes, and how important it is in relation to other URLs of the site. This allows search engines to crawl the site more efficiently and to find URLs that may be isolated from the rest of the site's content. The Sitemaps protocol is a URL inclusion protocol and complements robots.txt, a URL exclusion protocol. History Google first introduced Sitemaps 0.84 in June 2005 so web developers could publish lists of links from across their sites. Google, Yahoo! and Microsoft announced joint support for the Sitemaps protocol in November 2006. The schema version was changed to "Sitemap 0.90", but no other changes were made. In April 2007, Ask.com and IBM announced support for Sitemaps. Also, Google ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Web Crawler
A Web crawler, sometimes called a spider or spiderbot and often shortened to crawler, is an Internet bot that systematically browses the World Wide Web and that is typically operated by search engines for the purpose of Web indexing (''web spidering''). Web search engines and some other websites use Web crawling or spidering software to update their web content or indices of other sites' web content. Web crawlers copy pages for processing by a search engine, which indexes the downloaded pages so that users can search more efficiently. Crawlers consume resources on visited systems and often visit sites unprompted. Issues of schedule, load, and "politeness" come into play when large collections of pages are accessed. Mechanisms exist for public sites not wishing to be crawled to make this known to the crawling agent. For example, including a robots.txt file can request bots to index only parts of a website, or nothing at all. The number of Internet pages is extremely large; ev ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Sitemap
A sitemap is a list of pages of a web site within a domain. There are three primary kinds of sitemap: * Sitemaps used during the planning of a website by its designers. * Human-visible listings, typically hierarchical, of the pages on a site. * Structured listings intended for web crawlers such as search engines. Types of sitemaps Sitemaps may be addressed to users or to software. Many sites have user-visible sitemaps which present a systematic view, typically hierarchical, of the site. These are intended to help visitors find specific pages, and can also be used by crawlers. They also act as a navigation aid by providing an overview of a site's content at a single glance. Alphabetically organized sitemaps, sometimes called site indexes, are a different approach. For use by search engines and other crawlers, there is a structured format, the XML Sitemap, which lists the pages in a site, their relative importance, and how often they are updated. This is pointed to from the r ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
User-agent
In computing, a user agent is any software, acting on behalf of a user, which "retrieves, renders and facilitates end-user interaction with Web content". A user agent is therefore a special kind of software agent. Some prominent examples of user agents are web browsers and email readers. Often, a user agent acts as the client in a client–server system. In some contexts, such as within the Session Initiation Protocol (SIP), the term ''user agent'' refers to both end points of a communications session. User agent identification When a software agent operates in a network protocol, it often identifies itself, its application type, operating system, device model, software vendor, or software revision, by submitting a characteristic identification string to its operating peer. In HTTP, SIP,RFC 3261, ''SIP: Session Initiation Protocol'', IETF, The Internet Society (2002) and NNTP protocols, this identification is transmitted in a header field ''User-Agent''. Bots, such as Web cra ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Internet Bot
An Internet bot, web robot, robot or simply bot, is a software application that runs automated tasks (scripts) over the Internet, usually with the intent to imitate human activity on the Internet, such as messaging, on a large scale. An Internet bot plays the client role in a client–server model whereas the server role is usually played by web servers. Internet bots are able to perform tasks, that are simple and repetitive, much faster than a person could ever do. The most extensive use of bots is for web crawling, in which an automated script fetches, analyzes and files information from web servers. More than half of all web traffic is generated by bots. Efforts by web servers to restrict bots vary. Some servers have a robots.txt file that contains the rules governing bot behavior on that server. Any bot that does not follow the rules could, in theory, be denied access to or removed from the affected website. If the posted text file has no associated program/software/app, then ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Email Address Harvesting
Email harvesting or scraping is the process of obtaining lists of email addresses using various methods. Typically these are then used for bulk email or spam. Methods The simplest method involves spammers purchasing or trading lists of email addresses from other spammers. Another common method is the use of special software known as "harvesting bots" or "harvesters", which spider Web pages, postings on Usenet, mailing list archives, internet forums and other online sources to obtain email addresses from public data. Spammers may also use a form of dictionary attack in order to harvest email addresses, known as a directory harvest attack, where valid email addresses at a specific domain are found by guessing email address using common usernames in email addresses at that domain. For example, trying alan@example.com, alana@example.com, @example.com, etc. and any that are accepted for delivery by the recipient email server, instead of rejected, are added to the list of theoreticall ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Web Robot
An Internet bot, web robot, robot or simply bot, is a software application that runs automated tasks (scripts) over the Internet, usually with the intent to imitate human activity on the Internet, such as messaging, on a large scale. An Internet bot plays the client role in a client–server model whereas the server role is usually played by web servers. Internet bots are able to perform tasks, that are simple and repetitive, much faster than a person could ever do. The most extensive use of bots is for web crawling, in which an automated script fetches, analyzes and files information from web servers. More than half of all web traffic is generated by bots. Efforts by web servers to restrict bots vary. Some servers have a robots.txt file that contains the rules governing bot behavior on that server. Any bot that does not follow the rules could, in theory, be denied access to or removed from the affected website. If the posted text file has no associated program/software/app, then a ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Cloaking
Cloaking is a search engine optimization (SEO) technique in which the content presented to the search engine spider is different from that presented to the user's browser. This is done by delivering content based on the IP addresses or the User-Agent HTTP header of the user requesting the page. When a user is identified as a search engine spider, a server-side script delivers a different version of the web page, one that contains content not present on the visible page, or that is present but not searchable. The purpose of cloaking is sometimes to deceive search engines so they display the page when it would not otherwise be displayed (black hat SEO). However, it can also be a functional (though antiquated) technique for informing search engines of content they would not otherwise be able to locate because it is embedded in non-textual containers, such as video or certain Adobe Flash components. Since 2006, better methods of accessibility, including progressive enhancement, have ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Martijn Koster
Martijn Koster (born ca 1970) is a Dutch software engineer noted for his pioneering work on Internet searching. Koster created ALIWEB, the Internet's first search engine, which was announced in November 1993 while working at Nexor and presented in May 1994 at the First International Conference on the World Wide Web. Koster also developed ArchiePlex, a search engine for FTP sites that pre-dates the Web, and CUSI, a simple tool that allowed you to search different search engines in quick succession, useful in the early days of search when services provided varying results. Koster also created the Robots Exclusion Standard The robots exclusion standard, also known as the robots exclusion protocol or simply robots.txt, is a standard used by websites to indicate to visiting web crawlers and other web robots which portions of the site they are allowed to visit. Th .... References Living people Dutch software engineers Dutch computer scientists 1970 births {{N ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Google
Google LLC () is an American multinational technology company focusing on search engine technology, online advertising, cloud computing, computer software, quantum computing, e-commerce, artificial intelligence, and consumer electronics. It has been referred to as "the most powerful company in the world" and one of the world's most valuable brands due to its market dominance, data collection, and technological advantages in the area of artificial intelligence. Its parent company Alphabet is considered one of the Big Five American information technology companies, alongside Amazon, Apple, Meta, and Microsoft. Google was founded on September 4, 1998, by Larry Page and Sergey Brin while they were PhD students at Stanford University in California. Together they own about 14% of its publicly listed shares and control 56% of its stockholder voting power through super-voting stock. The company went public via an initial public offering (IPO) in 2004. In 2015, Google was reor ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Archive Team
Archive Team is a group dedicated to digital preservation and web archiving that was co-founded by Jason Scott in 2009. Its primary focus is the copying and preservation of content housed by at-risk online services. Some of its projects include the partial preservation of GeoCities, Yahoo! Video, Google Video, Splinder, Friendster, FortuneCity, TwitPic, SoundCloud, and the "Aaron Swartz Memorial JSTOR Liberator". Archive Team also archives URL shortener services and wikis on a regular basis. According to Jason Scott, "Archive Team was started out of anger and a feeling of powerlessness, this feeling that we were letting companies decide for us what was going to survive and what was going to die." Scott continues, "it's not our job to figure out what's valuable, to figure out what's meaningful. We work by three virtues: rage, paranoia and kleptomania." Warrior/Tracker system Archive Team is composed of a loose community of independent contributors/users. Their archival process ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
National Institute Of Standards And Technology
The National Institute of Standards and Technology (NIST) is an agency of the United States Department of Commerce whose mission is to promote American innovation and industrial competitiveness. NIST's activities are organized into physical science laboratory programs that include nanoscale science and technology, engineering, information technology, neutron research, material measurement, and physical measurement. From 1901 to 1988, the agency was named the National Bureau of Standards. History Background The Articles of Confederation, ratified by the colonies in 1781, provided: The United States in Congress assembled shall also have the sole and exclusive right and power of regulating the alloy and value of coin struck by their own authority, or by that of the respective states—fixing the standards of weights and measures throughout the United States. Article 1, section 8, of the Constitution of the United States, ratified in 1789, granted these powers to the new Congr ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
