Firefox is a free, multiplatform browser. Its popularity is second only to Microsoft's Internet Explorer among Web browsers, but unlike IE, it has open-source code. The result has been an avid development community, filled with people eager to squash bugs and create new functionality. Firefox also has the option to create and use extensions that can add new features or services right on top of the user experience. These add-ons have gotten so popular that Firefox creator Mozilla has created its own directory for users to search and sort through them. The latest release of Firefox has integrated some of these extensions, and Mozilla will continue to do so in future developments.
