What Is A 7Z File (And How Do I Open One)?

You have almost certainly encountered archived files at some point—ZIP, RAR, and so on. They look like a single file, but act a lot more like a package, letting people bundle and compress multiple files and folders into a single, smaller file. 7Z files work the same way, and are particular to the popular 7-Zip compression tool.
by Brady Gavin via How-To Geek