Browser extension into pages. Researchers have identified 50,870 Google Chrome extensions and 34,407 programs that injected ads. Thirty-eight percent of extensions and 17 percent of programs were catalogued as malicious software, the rest being potentially unwanted adware. Browser extension A browser extension is a plug-in that extends the functionality of a web browser. Some extensions are authored using web technologies such as HTML, JavaScript, and CSS. Others are developed using machine code and application programming interfaces (APIs) provided by web browsers, such as NPAPI and PPAPI. Browser extensions can change the user interface of the web browser without directly affecting viewable content
History of the web browser boom of the 1990s. Today, the major web browsers are Chrome, Safari, Internet Explorer, Firefox, Opera, and Edge. The explosion in popularity of the Web was triggered in September 1993 by NCSA Mosaic, a graphical browser which eventually ran on several popular office and home computers. This was the first web browser aiming to bring multimedia content to non-technical users, and therefore included images and text on the same page, unlike previous browser designs; its founder, Marc Andreessen, also established the company that in 1994, released Netscape Navigator, which resulted in one of the early browser wars, when it ended