SeaMonkey is Web-browser, advanced e-mail, newsgroup and feed client, IRC chat, and HTML editing made simple—all your Internet needs in one application.

• Sync allows you to keep your browsing history, passwords, bookmarks, preferences and tabs in sync across different devices (computers) in a secure way.
• Tabbed browsing gives you a better way to surf the net. You no longer have to open one page at a time. With tabbed browsing, open several pages at once with one click. Plus, your homepage can be multiple pages, in tabs. And if you mistakenly close a tab or window, functionality to Undo Closed Tab or Window helps you bring it back to continue working with it.
• Session restore brings back all your open windows and tabs after the rare occasion that SeaMonkey crashes—and if you wish even when you close and reopen the browser or restart your computer. But crashes should me rare nowadays since a crashing plugin will not take the whole application down anymore.
• Lightweight themes (Personas) let you give your SeaMonkey a personal touch through simple theming.
• Feed detection notifies you when web pages offer RSS or Atom feeds, and feed preview lets you view their contents and choose a reader with which to subscribe to those—including an internal reader in the Mail & Newsgroups component of SeaMonkey.
• Smart Location Bar enables you to search your visited web pages right when typing in the browser's location bar and finding what you want to re-visited as fast as possible by learning which pages you visit frequently.
• Popup blocker lets you surf the web without interruption from annoying ads.
• Find as you type gives you another way to navigate a page. Just start typing to jump from link to link or to find a word or phrase within a page.
• Safe Mode can help you solve problems that might occur, e.g. with incompatible add-ons. If you need to ask someone for support, the Troubleshooting Information page provides quick access to basic technical information.
• Plus all the features a modern browser should have, including: Advanced security settings, download management, web form autocompletion, themes, toolbar customization, multi-language and multi-platform support, plus the latest in web standards.