Polaroid: SX-70

When: 1972-1977
Why: First truly folding SLR camera, First instant-film SLR camera.

Apparently Polaroid had to create an SLR camera for their instant film. Luckily they made it really portable, and it became somewhat popular. There were many variations later (I was able to find at least 28 different models). There were also non-folding models of SX-70 and numerous international versions which were similar to the USA models. SX-70 model lines were manufactured until 1986 (1982 by some sources), and the compatible film was discontinued in 2006.

Polaroid: Land Camera Model 95

When: 1948
Why: first commercially available instant picture camera.

This is the first Polaroid model, and an instant hit on the market. Camera was easy to use, black/white (actually brown/white) photo was ready in one minute, almost automatic (only 8 settings of shutter/aperture) usage. It's not the first instant camera, by no means, but it's the first successful and mass-produced camera. You can find a remarkable description of the camera at The Land List web-site.

The first instant photo camera was actually the "Patent Camera Box" (1857) by Bolles & Smith, also American company. It was a wooden-box, wet plates camera, but it was not very successful on the market.