Instant film as we know it was invented by Edwin Land, founder of Polaroid, in 1948. This peel-apart film was finicky, sticky, and temperamental but accomplished the goal of having a print of your photo instantly.
It wasn’t until 1972 that Polaroid unveiled the SX-70, which combined all necessary chemicals into one package. All instant film since then is derived from this Polaroid technology.
While Polaroid ceased production of instant film in 2008, Fujifilm has kept the medium around with their line of Instax cameras and film. These cameras were popular enough to convince Polaroid to re-invest in instant technology as well.