Yes. It used to be easy.
Controlled Airspace (CTA) and Outside Controlled Airspace (OCTA).
Control zones, GAAP zones and uncontrolled airports.
FULLSAR if you want it, and at larger aerodromes a nice Air Traffic Officer to check your plan, give you the right NOTAMs and see you on your way.
Then some people wanted to fly in CTA without clearance if they were VFR, and not worry about planning if they were OCTA.
So we got:
Class A, and Class G
and Class C and Class D and CTAFs and MTAFs - a bunch of letters that weren't intuitive and no one to help and AVFAX for NOTAMs so that no one knew what they were doing or who they were supposed to talk to, or how much to plan or where - unless they were in the industry (and even then, only in the bit of sky they were flying in).
... and it all got so political and difficult that private pilots left the industry in droves and bought a boat instead.
