A Web browser is a program used to visit websites, while a search engine is a website that allows you to look for specific websites or information based on keywords, dates and other criteria. Common examples of Web browsers include Internet Explorer, Safari, Firefox and Chrome. Common examples of search engines include Google, Yahoo!, Bing and Ask.
The first Web browser to gain mainstream popularity was Mosaic. Released in 1993, this browser was developed by computer scientists at the University of Illinois at Urbana-Champaign and introduced many of the basic features still used today. After the Mosaic project ended, many Mosaic developers went on to help develop Netscape Navigator, a browser that remained in use until 2007 and was the predecessor of the still-popular Firefox browser.
Following the development of Web browsers, users needed a way to quickly find the exact information they needed, which led to the advent of search engines like AltaVista, WebCrawler and Yahoo. Before search engines, users would have to browse through online directories and guess which sites might have the information they needed.