The .rar file extension indicates that the archive is compressed using the RAR (Roshal ARchive) format. To access the contents, you'll need to extract the files using a compatible archiver, such as WinRAR or 7-Zip.
Assume you have a legitimate backup of a CD you own, or you’re exploring fan-made compilations that are copyright-free (e.g., college a cappella covers). Here is the safe method: Various Artists - Wicked The Soundtrack.rar