Many fan-made texture packs or lighting mods are distributed in RAR format to keep the file sizes manageable.

If you’ve come across a Tomb.Raider.Anniversary.rar file, you’re likely looking at a digital archive of the game. Because the game has transitioned across so many platforms—from the original PC and PS2 releases to modern digital storefronts—compressed files (like .rar) have become common in the community for several reasons:

Enthusiasts use archives to store specific versions of the game, including the Core Design "Cancelled" Edition files that were recently made available for research.