RAR files are used for high-efficiency compression, error recovery, and splitting large datasets into smaller, manageable parts.

Downloading RAR files from the internet carries inherent risks, as they are frequently used as "attack vectors" by malicious actors. How To Open, Create, and Convert RAR Files - AVG AntiVirus

If you have downloaded an "NLRSM.rar" file, you should know how the format works:

Unlike ZIP files, Windows and macOS do not natively support RAR files. You will need third-party software such as: WinRAR (the official tool). 7-Zip (a popular free and open-source alternative). Security Considerations