My first would have been a Humbrol "airbrush" back in the mid 70's. This was very similar to the Badger 250 series. more like a garden sprayer than an airbrush. It did actually have a cam arrangement around the air nozzle which could be rotated to limit how far the button went down, for a limited amount of air pressure control.
Second, a Badger 350, still using canned air. It was around this time that I discovered the tyre valve adaptor. Spray for about 1 minute, pump for 5 minutes, spray for 1 minute - I think you get the picture. I think I actually wore out that foot pump - eventually it had a groove in the back where the rod goes into the cylinder rather than a central hole. Air out of a car tyre also has the most wonderful cat pee-like aroma. Still it was cheaper than canned air. Unfortunately the old 350 seems to have gone.
Next was a Badger 200, which was my introduction to internal mix airbrushes. By this time I had acquired a compressor, and this was another huge leap. After being accustomed to canned air, the ability to vary your air pressure was simply amazing. However, I think I only used it a handful of times before having an extended break from modelling.
After returning to modelling, I did, out of interest, pick up a $30.00 Chinese made Badger 150 lookalike. While it does work, I think I only test-sprayed it once and it's remained in its box.
Up to this point, they were all siphon feed brushes which required a considerable amount of time and care in cleaning.
Enter my current "workhorse", a Sparmax SP-35C, a gravity feed, double action model. I can use as little as a couple of drops of paint (less paint than I would lose cleaning one of the above a/b's) and it takes very little effort to clean.