CS50 (Computer Science 50) is an introductory course on

computer science Computer science is the study of computation, information, and automation. Computer science spans Theoretical computer science, theoretical disciplines (such as algorithms, theory of computation, and information theory) to Applied science, ...

taught at

Harvard University Harvard University is a Private university, private Ivy League research university in Cambridge, Massachusetts, United States. Founded in 1636 and named for its first benefactor, the History of the Puritans in North America, Puritan clergyma ...

by David J. Malan. The on-campus version of the course is Harvard's largest class with 800 students, 102 staff, and up to 2,200 participants in their regular

hackathon A hackathon (also known as a hack day, hackfest, datathon or codefest; a portmanteau of '' hacking'' and ''marathon'') is an event where people engage in rapid and collaborative engineering over a relatively short period of time such as 24 or 48 h ...

s. The course was first offered on campus in 1989, and Malan has been the course's instructor since 2007. Notable industry experts including

Mark Zuckerberg Mark Elliot Zuckerberg (; born May 14, 1984) is an American businessman who co-founded the social media service Facebook and its parent company Meta Platforms, of which he is the chairman, chief executive officer, and controlling sharehold ...

and

Steve Ballmer Steven Anthony Ballmer (; March 24, 1956) is an American businessman and investor who served as chief executive officer of Microsoft from 2000 to 2014. He is the owner of the Los Angeles Clippers of the National Basketball Association (NBA). He i ...

have given guest lectures. An online version of the course, CS50x, is available through the platforms

edX edX is an American For-profit higher education in the United States, for-profit massive open online course provider. It was founded by MIT and Harvard. It is a subsidiary of 2U (company), 2U. History edX was founded in May 2012 by the admi ...

and

OpenCourseWare OpenCourseWare (OCW) are course lessons created at universities and published for free via the Internet. OCW projects first appeared in the late 1990s, and after gaining traction in Europe and then the United States have become a worldwide means ...

and follows the same curriculum as the in-person format of the course. All CS50x course materials are free and there is no fee to complete the course, though various verified certificates are available for a fee. CS50x teaches the languages C,

Python Python may refer to: Snakes * Pythonidae, a family of nonvenomous snakes found in Africa, Asia, and Australia ** ''Python'' (genus), a genus of Pythonidae found in Africa and Asia * Python (mythology), a mythical serpent Computing * Python (prog ...

SQL Structured Query Language (SQL) (pronounced ''S-Q-L''; or alternatively as "sequel") is a domain-specific language used to manage data, especially in a relational database management system (RDBMS). It is particularly useful in handling s ...

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 ( ...

, CSS, and

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 ...

. It also teaches fundamental computer science concepts including

data structure In computer science, a data structure is a data organization and storage format that is usually chosen for Efficiency, efficient Data access, access to data. More precisely, a data structure is a collection of data values, the relationships amo ...

s and the

Flask Flask may refer to: Container * Hip flask, a small container used to carry liquid * Laboratory flask, laboratory glassware for holding larger volumes than simple test tubes ** Erlenmeyer flask, a common laboratory flask with a flat bottom, a c ...

framework. New content is added to the course each year; additional lectures on

cybersecurity Computer security (also cybersecurity, digital security, or information technology (IT) security) is a subdiscipline within the field of information security. It consists of the protection of computer software, systems and networks from thr ...

and

emoji An emoji ( ; plural emoji or emojis; , ) is a pictogram, logogram, ideogram, or smiley embedded in text and used in electronic messages and web pages. The primary function of modern emoji is to fill in emotional cues otherwise missing from type ...

were added for 2022. Another adapted version of the course, CS50 AP, is designed for high school students and completes the required curriculum of

AP Computer Science Principles Advanced Placement (AP) Computer Science Principles (also known as AP CSP) is an AP Computer Science course and examination offered by the College Board under the Advanced Placement program. The course is designed as an equivalent to a first-sem ...

History

CS50 was first available in 1989. Michael D. Smith was the professor of the course from 2002 to 2006, after which point David J. Malan has been the primary professor.

Margo Seltzer Margo Ilene Seltzer is an American computer scientist. She is currently the Canada 150 Research Chair in Computer Systems and the Cheriton Family Chair in Computer Science at the University of British Columbia. Previously, Seltzer was the Herchel ...

, Brian Yu, and Doug Lloyd have also taught the course. Guest lecturers have included

(2005) and

(2014).

Yale University Yale University is a Private university, private Ivy League research university in New Haven, Connecticut, United States. Founded in 1701, Yale is the List of Colonial Colleges, third-oldest institution of higher education in the United Stat ...

began offering the course in 2015, becoming the second institution to teach an official version of the course. The course was offered experimentally for three years until it was added as a permanently-available course. At Yale, CS50 is based on Malan's recorded lectures, which are then supplemented by in-person class sections and office hours, all in

New Haven New Haven is a city of the U.S. state of Connecticut. It is located on New Haven Harbor on the northern shore of Long Island Sound. With a population of 135,081 as determined by the 2020 U.S. census, New Haven is the third largest city in Co ...

. The

University of Oxford The University of Oxford is a collegiate university, collegiate research university in Oxford, England. There is evidence of teaching as early as 1096, making it the oldest university in the English-speaking world and the List of oldest un ...

is the third university to offer the course; it is available as an online course through their Department for Continuing Education. In 2016, CS50's lecture schedule changed so that students would only have to attend two in-person lectures during the semester. Instead, lectures are now primarily delivered online. In 2023, an AI-powered teaching assistant was introduced to the course.

Course progression

CS32 (Computational Thinking and Problem Solving), taught by Michael D. Smith, is an alternative to CS50 but does not have a free online version. The next course in sequence after CS32 or CS50 is CS51: Abstraction and Design in Computation, instructed by

Stuart M. Shieber Stuart may refer to: People *Stuart (name), a given name and surname (and list of people with the name) * Clan Stuart of Bute, a Scottish clan *House of Stuart, a royal house of Scotland and England Places Australia Generally *Stuart Highway, ...

with Brian Yu as co-instructor. CS50 is primarily offered every fall semester, with CS51 being offered every spring semester.

CS50x

CS50x is a massive online open course and "one of the most popular MOOCs in the world." CS50 first opened to online students in 2007, but the CS50x course officially launched in 2012 as a course on

. The course content can also be taken through

for those not seeking a verified certificate. In its inaugural year, over 50 thousand students enrolled; in the years since, it has become the largest MOOC on the edX platform. In 2016, it was reported that around 700 thousand students were enrolled in CS50x. In 2018, a freeCodeCamp article crowned CS50x as "the best MOOC."

Format

There are 11 weeks of material in the CS50x course. Recordings of the on-campus lectures are created and uploaded to multiple platforms, including

YouTube YouTube is an American social media and online video sharing platform owned by Google. YouTube was founded on February 14, 2005, by Steve Chen, Chad Hurley, and Jawed Karim who were three former employees of PayPal. Headquartered in ...

Apple TV Apple TV is a digital media player and a microconsole developed and marketed by Apple. It is a small piece of networking hardware that sends received media data such as video and audio to a TV or external display. Its media services include ...

, and Google TV (one lecture per week). Additional recommended "section" and "shorts" videos are available, as well as "walkthrough" videos within the problem sets. After each week's material, the student submits a problem set, which automatically receives a calculated grade. At the end of the course, the student must submit a final project to complete the course or receive a verified certificate.

Other CS50 courses

There are a variety of other CS50 courses available on

and

, including courses on

, R, and

, as well as CS50 AI and CS50 Web, with focuses on

artificial intelligence Artificial intelligence (AI) is the capability of computer, computational systems to perform tasks typically associated with human intelligence, such as learning, reasoning, problem-solving, perception, and decision-making. It is a field of re ...

and

web applications A web application (or web app) is application software that is created with web technologies and runs via a web browser. Web applications emerged during the late 1990s and allowed for the server to dynamically build a response to the request, ...

, respectively.

Notes

References

External links

CS50 official website

Complete List of CS50 Courses

* CS50x: CS50's Introduction to Computer Science
edX

OpenCourseWare
* CS50 AI: CS50's Introduction to Artificial Intelligence with Python
edX

OpenCourseWare
* CS50 Business: CS50's Computer Science for Business Professionals
edX

OpenCourseWare
* CS50 Cybersecurity: CS50's Introduction to Cybersecurity
edX

OpenCourseWare
* CS50 for Lawyers: CS50's Computer Science for Lawyers
edX

OpenCourseWare
* CS50 Python: CS50's Introduction to Programming with Python
edX

OpenCourseWare
* CS50 R: CS50's Introduction to Programming with R
edX

OpenCourseWare
* CS50 Scratch: CS50's Introduction to Programming with Scratch
edX

OpenCourseWare
* CS50 SQL: CS50's Introduction to Databases with SQL
edX

OpenCourseWare
* CS50 Web: CS50's Web Programming with Python and JavaScript
edX

OpenCourseWare
!--https://cdn.cs50.net/2007/fall/lectures/0/syllabus.pdf --> 1989 establishments in the United States Computer science education Lecture series at Harvard University Yale University Lecture series at the University of Oxford University and college lecture series