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
Web browser the browser. Virtually all URLs on the Web start with either "http:" or "https:" which means the browser will retrieve them with the Hypertext Transfer Protocol. In the case of "https:" the communication between the browser and the web server is encrypted for the purposes of security and privacy. Another URL prefix is "file:" which is used to display local files already stored on the user's device. Once a web page has been retrieved, the browser's rendering engine displays it on the user's device. This includes image and video formats supported by the browser. Web pages usually contain hyperlinks to