SeaMonkey is the all-in-one internet application suite (formerly known as the Mozilla Application Suite), containing a web browser, a mail and newsgroups client, an HTML editor, web development tools, and an IRC chat client in a single software package.

The SeaMonkey project is a community effort to develop the SeaMonkey all-in-one internet application suite. Such a software suite was previously made popular by Netscape and Mozilla, and the SeaMonkey project continues to develop and deliver high-quality updates to this concept.