Firefox supports tabbed browsing, which allows users to open multiple pages in the same window. This feature was carried over from the Mozilla Application Suite, which in turn had borrowed the feature from the popular MultiZilla extension for Mozilla.
Firefox also permits the “homepage” to be a list of URLs delimited with vertical bars (|), which are automatically opened in separate tabs, rather than a single page.
Firefox 2 supports more tabbed browsing features, including a “tab overflow” solution that keeps the user’s tabs easily accessible when they don’t fit horizontally, “session store” which lets the user keep the opened tabs across the restarts, the “undo close tab” feature, etc