: Right-click and choose "Add to archive..." in WinRAR.
: Use a free utility like The Unarchiver from the App Store.
Right-click Asss.rar and select or "Extract to Asss/" to create a folder with the contents.
The file likely refers to the "all entities" version of the ASSS (A Standalone Subspace Server) complete documentation, which is a standalone server for the game Subspace .
If the archive contains .ass files, these are subtitle files often used for anime or karaoke.
: Open them with media players like VLC Media Player or MPlayer . Editing : Use Aegisub to modify styles, fonts, and timing.