The file is a compressed archive file, likely containing data, software, or media that has been bundled together to reduce its total size for easier sharing or storage.

The .rar extension indicates it was created using or a similar compression tool. To see what is inside and use the actual files, you will need to "extract" or "unzip" them. How to open "ca171.rar" Need to open, create, or convert a RAR file? - WinZip