98
~~Most~~ many file types are just a renamed .zip
(lemmy.blahaj.zone)
A "Showerthought" is a simple term used to describe the thoughts that pop into your head while you're doing everyday things like taking a shower, driving, or just daydreaming. The best ones are thoughts that many people can relate to and they find something funny or interesting in regular stuff.
Take a .docx file, using 7-zip, exctract it.
You will get an entire folder structure with several files inside the .docx file.
What OP means is that several programs use a zip file as a container for all the stuff they need in a save file.
The file extention is just a name for the OS to find the proper program to open the file.