UNIX is sublime
Or, "how to use a computer without hating yourself for it in the morning"
Or, "Unix is basically a simple operating system . . ."
Or, "My weariness and disdain for computers grow with each additional unit of knowledge"
Or, "Worse is better"
Origins
UNIX is not Multics
Multics = Multiplexed Information and Computer Service
UNIX = Uniplexed Information and Computing Service
The name 'UNIX' is a pun on the name 'Multics'. Multics was entirely too large and complicated to be useful so the boys at Bell Labs cooked up something smaller, less complicated, and easier to use.
Ancient emulation interlude
How to run Multics in 2022.
This wiki helped me emulate UNIXv5.
And this one helped me emulate UNIXv7.
These guys host ancient systems accessible via guest accounts over ssh.
"Cool, but useless."
I know almost nothing about Multics and I'm not sure if it's even worth learning. This is about UNIX, not Multics. Maybe I'll come back to it.
Philosophy, implementations, ducks
When I think of "UNIX", I do not think of the trademark. Instead, I think of the Unix philosophy. and the general design principles, interface, and behavior of a UNIX system.
A better way of thinking about "UNIX" is as something "POSIX-like" rather than "AT&T's commercial UNIX". Example: although Linux and GNU are overly complicated, they pass the duck test for being a UNIX. Pedigree or not, you know a nix when you see one.
Also, when I say "UNIX", I mean "Free UNIX". I have no interest in proprietary implementations that only exist for the purpose of restricting users and disempowering/discouraging sysadmins from becoming self-reliant.
So what is the philosophy?
Do one thing and do it well
Design programs that work together using text as the common interface
KISS: Keep it simple, stupid
Test early, test often
And additionally:
everything is a file or a process
Design
10,000 Ft View
UNIX is a multiuser time sharing networked operating system, running as an always online service. A UNIX system is a single mainframe computer running an operating system designed for multiple users to access concurrently over the network, equally (depending on implementation) sharing resources amongst the active users.
In a traditional network setup, there is one mainframe UNIX machine with multiple dumb terminals connected to it over the network. None of the users touch the mainframe physically. Instead, they interact with it exclusively through their own dumb terms. These dumb terminals have minimal or no computing power of their own because all of the actual computation takes place on the mainframe. Built in networking is a given.
As for the actual software running on the mainframe, it's quite simple to visualize. A Unix system is a flexible but organized stack of concepts, each depending on the concept below, all working together for the sole purpose of enabling the end user to play video games and watch videos online.
/ user applications