A web browser is a software program that allows a user to locate, access, and display web pages. In common usage, a web browser is usually shortened to "browser." Browsers are used primarily for displaying and accessing websites on the internet, as well as other content created using languages such as Hypertext Markup Language (HTML) and Extensible Markup Language (XML).
Browsers translate web pages and websites delivered using Hypertext Transfer Protocol (HTTP) into human-readable content. They also have the ability to display other protocols and prefixes, such as secure HTTP (HTTPS), File Transfer Protocol (FTP), email handling (mailto:), and files (file:). In addition, most browsers also support external plug-ins required to display active content, such as in-page video, audio and game content.
Techopedia explains Web Browser
A variety of web browsers are available with different features, and are designed to run on different operating systems. Common browsers include Internet Explorer from Microsoft, Firefox from Mozilla, Google Chrome, Safari from Apple, and Opera. All major browsers have mobile versions that are lightweight versions for accessing the web on mobile devices.
Web browsers date back to the late 1980s when an English scientist, Tim Berners-Lee, first developed the ideas that led to the World Wide Web (WWW). This consisted of a series of pages created using the HTML language and joined or linked together with pointers called hyperlinks. Following this was the need for a program that could access and display the HTML pages correctly – the browser.
In 1993, a new browser known as Mosaic was developed, which soon gained widespread usage due to its graphical-interface capability. Marc Andreesen, a member of the Mosaic development team, left in 1994 to develop his own commercial browser based on Mosaic. He called it Netscape Navigator, and it quickly captured over 90 percent of the nascent browser market. It soon faced stiff competition in 1995 from Microsoft's Internet Explorer, which was freely bundled with Windows 95 (and later versions of Windows). It was pointless to buy Navigator when Internet Explorer was free, and as a result, Navigator (and Netscape) were driven into the ground. But while Mosaic and Netscape are no longer around, the age of the browser was launched and continues to this day, as more and more applications move to the web