A PAK file is a package file created by different video games to archive game data. Essentially, it’s a game file format. This can include multiple game elements such as graphics, textures, sounds, objects, along with other game data. The archive is mostly saved as .zip file and can be extracted with popular decompression software such as WinZip and WinRAR. Examples of video games using PAK files include Quake, Hexen, Crysis, and Half-Life.
PAK File Format - More Information
In most cases, PAK files are saved in ZIP file format. But different applications may use different file format for storing these files.
A file with .pak extenion is a Simutrans transportation simulation game file format. It contains objects used in the simulation such as user made graphics and data contents. It can have several different objects such as game vehicles, buildings, terrain, etc. PAK files are generated using MakeObject, a utility that compiles .dat files and .png pictures for creating these simulation objects. Simutrans lets the players to run a successful transport system by constructing and managing transportation systems for passengers, mail and goods by land
How to Create PAK Files?
Simutrans has listed sample examples for creating PAK files on Windows and Linux OS.