: These archives are frequently used to hide malicious executables, keyloggers , or Trojans that can steal personal data or compromise your system.

Files ending in indicate a "split archive". Large game installers are often broken into smaller chunks (part1, part2, etc.) to make them easier to upload and download. You would need all parts in the set to successfully extract the game. Security Risks

: Unlike the official version on Steam , pirated copies do not receive automatic security patches or performance improvements.