The FreeSpace Port is a user-made FreeSpace 2 port of the main Descent: FreeSpace campaign, created by GalacticEmperor and Goober5000.
This download contains the official FreeSpace Open Installer, which will download and install the FreeSpace Port as well as FreeSpace Open and any other mods you choose. This tool requires Java, but will run on any operating system where Java is installed.