A web browser is a software made to browse the web. It's main purpose is to retrieve and render the documents available on the web and to allow its users to jump from one document to another through hyperlinks.
A bit of history
The first web browser was build by Tim Berners-Lee in 1990 and was first named WorldWideWeb.
The first wildly adopted web browser was Mozaic made by Marc Andreessen in 1993. One year later, he creates Netscape Navigator which gain a big 90% market share one year later.
By the end of the 90's, two web browsers were competing: Netscape Navigator and Microsoft Internet Explorer. This period between 1996 and 2000 is known as "The Browser War". Finally, with the release of Windows XP and Internet Explorer 6 by Microsoft and with Netscape acquired by AOL, Microsoft won that war with Internet Explorer getting 95% of market share.
A new generation of browser appears in 2004 with the release of Firefox and the opening of Apple Safari's code source. Since some new releases of Internet Explorer, and the release of Google Chrome in 2008 the market tend to be more balanced between those four browsers and the battle now stand on the mobile front.
At the very basics, a browser is at the heart of the web which means it handle three main functions:
- To access resources available on the Web: To that end, a web browser is able to understand URLs and to use the HTTP protocol, modern browsers also support Web Socket and WebRTC protocols.
- To surf through resources available on the Web: This required a browser to support the notion of hyperlinks which is a way to turn any regular text from a resource into a link that will tell the browser to open another resource.
After twenty years of evolution, the web browsers has evolved from resources reading software into full execution runtime. Now web pages are more than just plain documents to read, they are autonomous web applications that can be executed by web browsers