Use the official 7-Zip utility or alternatives like WinRAR.

Windows often warns you if a file was downloaded from a potentially unsafe internet source. 7zip Malware: Beware 7zip.com

Tools like PeaZip or the command-line p7zip package are standard. A Note on Security

It typically offers better compression ratios than standard ZIP files.

to ensure it came from a trusted sender or website.

A file is a container that holds one or more files in a compressed state to save space or make them easier to send.

Large data sets can be split into smaller chunks (e.g., .7z.001, .7z.002) for easier uploading. How to Open "Lgdkhtj.7z"

Applications like The Unarchiver or the Mac version of WinZip can handle .7z files.