A RAR file is a proprietary archive format that "shrinks" files to save space.

If you're looking for the technical side of what that download actually is:

You click it. The download is instantaneous, a blink of the browser’s progress bar. The icon sits on your desktop: a stack of three tiny books bound by a leather strap. You right-click.

Archive mastery with a classic workhorse WinRAR is a powerful file compressor and decompressor. It has been around for many years, How to Open RAR Files on Windows, Mac, and Mobile - Avast

The "449K rar" wasn't a resource or a tool. It was a digital time capsule—a weightless, compressed fragment of someone’s life, waiting for a decade for someone to finally "Extract" the memories. What is a .RAR file, anyway?

Always be careful when downloading small archives from unknown sites. Even a 449K file can contain scripts or malware that only "activate" once you extract them.

You usually need a dedicated tool. WinRAR is the most famous "classic" option, but 7-Zip or Unzip One also work for free.

RAR files are usually safe to use. But just like regular files, compressed files (RAR or ZIP) can also contain viruses or malware. How to open RAR files | Trend Micro Help Center