Oh my god I'm so old....
The first computer I ever had at HOME was a TRS-80 Model 1 Level 1 with 4K, which after 1 week, I replaced with a Model 1 Level II with 16k (Power!!).
The first computers I actually learned to program on however were the HP 2000F and UNIVAC (I forget the model number) mainframe computers.
These computers were time-share machines that connected a bunch of schools in the Montreal area at the time. Look at this sucker:
This is the "Terminal" that was used to program it. It had no screen, only a printer.
There was no software available to the students so we had to write our own. BBS's, message systems, etc.
One of the most fun things to do was to play Multi-player 2D and 3D Space War Games on it, that you played against other real humans from other schools in real time. You had a ship that you would navigate in 3D space. The game was all numbers - no graphics. It would list all of the other ships as well as their Speed / Course / Bearing / Range. Phasers, Torpedos, Damage etc was all expressed in numbers. You had to imagine what was going on. Somehow, it was fun as hell.
Graphics were presented as "ascii art". HUGE images were required because the resolution was so low and made up of characters like #$%^&*. Its data rate was only 300 bits per second, which means the FASTEST it could print was only 37 characters per second. Oh god I'm an old fart!