I, as somebody who knows basically nothing computers, have become sincerely confused from a lot of tutorials I have been reading about operating systems and hacking (no, not cracking). First, I thought I would use Unix, thinking that "Unix" was basically the same as a title like "Windows", and though it reffered to single operating system by a single company. Than I learned that no, it wasnt a single operating system, their was sunOS, FreeBSD, OpenBSD, and NetBSD. OK, now I got really confused. I went through the website and discovered their are a couple of pretty major differences between these different versions. This means that every time I read the word "Unix" it could refer to any of these or others, which led me very far astray. This entire story about Unix also goes for Linux when i looked it up. Is their a "general" version of Linux or Unix which is the one that these general Unix/Linuxtutorials are referring too? Any help on the subbject would be appreciated.

P.S. I would appreciate it if nobody gave me any really broad answers.