A browser is software, just like a word-processing or spreadsheet program, only instead of cranking out pie charts or memos, a browser enables you to see Web pages. Mosaic was the first browser, while Netscape Navigator and Microsoft Internet Explorer are the most commonly used nowadays. The advent of browsers transformed the Internet - formerly a dry, text-based thing only a government official or academician could love - into the colorful, user-friendly World Wide Web we know and use.

How it works: Browsers take text files written in HTML (which is the coding language that gussies up plain-old text with images, sound clips, and links to other Web pages) and assemble all the relevant pieces into one colorful, easy-to-digest page. Browsers can also host a variety of additional Internet fun: email, chat rooms, newsgroups, online gaming, and more.