Stack Overflow is a question-and-answer website for programmers. It is the flagship site of the Stack Exchange Network. It was created in 2008 by Jeff Atwood and Joel Spolsky. It features questions and answers on certain computer programming topics. It was created to be a more open alternative to earlier question and answer websites such as Experts-Exchange. Stack Overflow was sold to Prosus, a Netherlands-based consumer internet conglomerate, on 2 June 2021 for $1.8 billion.
The website serves as a platform for users to ask and answer questions, and, through membership and active participation, to vote questions and answers up or down similar to Reddit and edit questions and answers in a fashion similar to a wiki. Users of Stack Overflow can earn reputation points and "badges"; for example, a person is awarded 10 reputation points for receiving an "up" vote on a question or an answer to a question, and can receive badges for their valued contributions, which represents a gamification of the traditional Q&A website. Users unlock new privileges with an increase in reputation like the ability to vote, comment, and even edit other people's posts.
Stack Overflow has over 20 million registered users, and has received over 24 million questions and 35 million answers. The site and similar programming question and answer sites have globally mostly replaced programming books for day-to-day programming reference in the 2000s, and today are an important part of computer programming. Based on the type of tags assigned to questions, the top eight most discussed topics on the site are: JavaScript, Java, C#, PHP, Android, Python, jQuery, and HTML.
History
The website was created by Jeff Atwood and Joel Spolsky in 2008. The name for the website was chosen by voting in April 2008 by readers of Coding Horror, Atwood's popular programming blog. On 31 July 2008, Jeff Atwood sent out invitations encouraging his subscribers to take part in the private beta of the new website, limiting its use to those willing to test out the new software. On 15 September 2008 it was announced that the public beta version was in session and that the general public was now able to use it to seek assistance on programming related issues. The design of the Stack Overflow logo was decided by a voting process.
On 3 May 2010, it was announced that Stack Overflow had raised $6 million in venture capital from a group of investors led by Union Square Ventures.
In 2019, Stack Overflow named Prashanth Chandrasekar as its chief executive officer and Teresa Dietrich as its chief product officer.
In June 2021, Prosus, a Netherlands-based subsidiary of South African media company Naspers, announced a deal to acquire Stack Overflow for $1.8 billion.
Security breach
In early May 2019, an update was deployed to Stack Overflow's development version. It contained a bug which allowed an attacker to grant themselves privileges in accessing the production version of the site. Stack Overflow published on their blog that approximately 184 public network users were affected by this breach, which "could have returned IP address, names, or emails".
2023 controversy over AI-generated content and moderation strike
Content
Stack Overflow only accepts questions about programming that are tightly focused on a specific problem. Questions of a broader nature—or those inviting answers that are inherently a matter of opinion—are usually rejected by the site's users, and marked as closed. The sister site softwareengineering.stackexchange.com is intended to be a venue for broader queries, e.g. general questions about software development.
Closing questions is a main differentiation from other Q&A sites like Yahoo! Answers and a way to prevent low quality questions. The mechanism was overhauled in 2013; questions edited after being put "on hold" now appear in a review queue. Jeff Atwood stated in 2010 that duplicate questions are not seen as a problem but rather they constitute an advantage if such additional questions drive extra traffic to the site by multiplying relevant keyword hits in search engines.
All user-generated content is licensed under Creative Commons Attribute-ShareAlike license, version 2.5, 3.0, or 4.0 depending on the date the content was contributed.