Linux

Linux is an operating system like the previous ones I've mentioned before with one major difference: Linux is open-source. This means that it heavily relies on communities to add compatibility to the it. It comes in many "Flavours," like my personal favorite Arch, Debian, Ubuntu, Mint, and many many more. It can do almost everything windows does, include run windows things. Linux generally uses bash for its CLI but due to the nature of the system you can rip it out and use something like ZSH instead.