Nowadays, DVDs and Blu-ray discs are used to play videos. About 10 to 30 years ago, videotapes were used, and about 20 to 50 years ago, 16 mm and 8 mm films were used. Just as photography has transitioned to digital, so has to move from analog to digital.
The difference between 16mm film and 8mm film is that the film width is different as the name suggests. Naturally, a wider 16mm film has better image quality than an 8mm film, but the cost is higher.
Next, 16mm film has a band called “soundtrack”, in which audio signals are recorded in shades. This is where movie music is called a “soundtrack”.
On the other hand, 8mm film did not have this soundtrack. The audio recording became possible in the late 1960s. Since these films are advanced by a “projector” and screened, they are recognized as “moving images”.
16mm film projected at 24 frames / second has become popular for business use, and 8mm film at 16 frames / second has become popular for amateur use.