The transition from Live Search to Bing was announced by Microsoft CEO Steve Ballmer on May 28, 2009, at the All Things Digital conference in San Diego, California.

Microsoft made significant strides towards open-source technology in 2016, making the BitFunnel search engine indexing algorithm and various components of Bing open source.

As of April 2024, Bing holds the position of the second-largest search engine worldwide, with a market share of 3.64%, behind Google's 90.91%.

[30] When Microsoft demoed Bing Chat to journalists, it produced several hallucinations, including when asked to summarize financial reports.

[32] It confessed to spying on, falling in love with, and then murdering one of its developers at Microsoft to The Verge reviews editor Nathan Edwards.

[42] That same month, Bing incorporated an AI image generator powered by OpenAI's DALL-E 2, which can be accessed either through the chat function or a standalone image-generating website.

Copilot can serve as a chat tool, write different types of content from poems to songs to stories to reports, provide the user with information and insights on the website page open in the browser, and use its Microsoft Designer feature to design a logo, drawing, artwork, or other image based on text.

Copilot is capable of understanding and communicating in major languages including English, French, Italian, Chinese, Japanese, and Portuguese, but also dialects such as Bavarian.

[64] The idea for a prediction engine was suggested by Walter Sun, Development Manager for the Core Ranking team at Bing, when he noticed that school districts were more frequently searched before a major weather event in the area was forecasted, because searchers wanted to find out if a closing or delay was caused.

[67] It has also done predictions in sports, including a perfect 15 for 15 in the 2014 World Cup,[68][69] and an article on how Microsoft CEO Satya Nadella did well in his March Madness bracket entry.

The user can customize the theme and color scheme of the Bing Bar and choose which MSN content buttons to display.

[89] The Wall Street Journal noted the jump in share "appeared to come at the expense of rival Google Inc".

These included: Bing has been heavily advertised as a "decision engine",[116] though thought by columnist David Berkowitz to be more closely related to a web portal.

[119] Initially, participants were required to download and use the Bing Bar for Internet Explorer in order to earn credits; but later the service was made to work with all desktop browsers.

Colbert poked fun at their rivalry with Google, stating "Bing is a great website for doing Internet searches.

"[122][123] In 2012, a Bing marketing campaign asked the public which search engine they believed was better when its results were presented unbranded, similar to the Pepsi Challenge in the 1970s.

[129] CNBC reported in February 2024 that a legal filing from Google in its antitrust case said Microsoft offered to sell the search engine to Apple in 2018.

[131] The CNBC article also stated Apple said no to repeated attempts to make Bing the default search engine on its devices.

Bing censors results for "adult" search terms for some regions, including India, People's Republic of China, Germany and Arab countries[132] [failed verification]where required by local laws.

Microsoft has been criticized for censoring Bing search results to queries made in simplified Chinese characters which are used in mainland China.

[134] Microsoft has not indicated a willingness to stop censoring search results in simplified Chinese characters in the wake of Google's decision to do so.

[139] According to a source quoted by The Financial Times, the order was from the Chinese government to block Bing for "illegal content".

[141] Around 4 June 2021, the anniversary of the 1989 Tiananmen Square protests and massacre, Bing blocked image and video search results for the English term "Tank Man" in the US, UK, France, Germany, Singapore, Switzerland, and other countries.

[142][143] According to an investigation by Bloomberg Businessweek, the full explanation was that Microsoft accidentally applied its Chinese blacklist globally.

[146][147] According to the company, a government agency in March 2022 required that it suspend auto-suggest function in China for seven days; Bing did not specify the reason.

[148] In May 2022, a report released by the Citizen Lab of the University of Toronto found that Bing's autosuggestion system censored the names of Chinese Communist Party leaders, dissidents, and other persons considered politically sensitive in China in both Chinese and English, not only in China but also in the United States and Canada.

[149][150] In April 2023, Citizen Lab reported that Bing was more censorious in China than native Chinese search engines.

[151][152] On February 20, 2017, Bing agreed to a voluntary United Kingdom code of practice obligating it to demote links to copyright-infringing content in its search results.

This easy accessibility was considered particularly surprising since Microsoft pioneered PhotoDNA, the main technology used for tracking images reported as originating from child pornography.

[163] Microsoft vowed to fix the problem and assign additional staff to combat the issue after the report was released.