Mozilla Firefox is a free, open-source and cross-platform web browser
for Windows, Linux, MacOS X and many other operating systems. It is
small, fast and easy to use, and offers many advantages over other web
browsers, such as tabbed browsing and the ability to block pop-up
windows.

Firefox also offers excellent bookmark and history management, and it
can be extended by developers using industry standards such as XML,
CSS, JavaScript, C++, etc. Many extensions are available.