We normally need to compress or decompress digital files on computer or other devices. Sometimes we call compress and decompress as zip and unzip.
If you use Windows system, ie, Windows 10, you can directly zip and unzip files or folders because Windows 10 provides built-in Zip and Unzip functions. Just right click selected file(s) or selected folder, click Send to menu item, and select Compressed (zipped) folder, you will get a compressed file.
If you want to decompress .zip file on Windows, right click the zip file, select Extract All… item to unzip it.