RAR for DOS is the DOS version of the popular WinRAR utility. If you're playing DOS games on a real DOS computer, you'll need an archive program to unzip the files, and ancient copies of PKUnzip may not be able to unpack newer ZIP archives, and it certainly won't be recognize newer formats like RAR and 7z. RAR 3.93 can decompress anything that WinRAR 3.93 can. RARLAB will no longer release new versions of RAR for DOS; this is the last version of RAR. Newer versions for Windows, Pocket PC, Linux, FreeBSD, and Mac OS X are available on the author's website.