In order to work with zipped files, they must be unzipped or extracted first. Windows has a built in program called Windows Compressed Folders which can do this for you. If you have installed a zip program, such as WinZip or 7-Zip, Windows Compressed Folders may not be easily available on your computer. If you follow the instructions below for Windows Compressed Folders, but a different program opens, you can still follow the instructions listed, and it should generally still work.
To zip a file, find the file in Windows Explorer (file browser).
Right-click on the file, left-click on Send To > , then left-click on Compressed (Zipped) Folder:
Windows creates a temporary file (highlighted letters) and may show a "Compressing..." progress box:
When Windows finishes compression, a new .zip file has been created in the same folder as your unzipped file, with the same name except with a .zip extension:
Note that in most cases, the file size will be much smaller. Some files can't be compressed much, such as .jpg pictures. Others files, such as text and database files, compress to a small fraction of the size of the uncompressed file.