Dobsonian
Also called: Dob, truss Dobsonian.
A Newtonian reflector on a simple rocking-box mount — the easiest way to get a big aperture.
John Dobson popularised the design in the 1960s and 70s on San Francisco's sidewalks: a Newtonian tube in a plywood box that swivels and tilts on Teflon pads. You point it by hand. It's simple, stable and cheap, so a Dobsonian puts 8, 12 or 16 inches of aperture within reach. Big ones break down into a truss of poles for transport.
Most are fast (f/4–f/6), so they show coma at the field edge and benefit from a coma corrector; they don't track the sky on their own.