1888, Kodak Company of the United States began to produce film and made the world's first camera using film. At that time, the film used for the camera was very long, and it could take 65 mm 100 negatives. The customer bought the camera and the film was packed in advance. After taking pictures, they need to be sent back to Kodak with the camera for development. The birth of new photosensitive materials promoted the development of photographic equipment, and then cameras with various specifications of film came out one after another. 1900, Frank A.Brownell designed a compact cassette camera for Kodak Company, which was called Brownell1. This camera uses the film numbered 1 17, and the film is attached with protective paper, which can be loaded and unloaded during the day (you can take 6 photos of 57x57mm at a time, and the operation is quite simple. In 190 1, Brownie designed Brownie No.2 camera with a screen size of 57x83 and a film number of 120. This type of camera was very popular at that time. Brownie camera has been improved several times and has been produced until 1935.

The appearance of new cameras requires new specifications of film. Kodak Company started with the film number 1895 10 1, and has 30 numbered film products in just 20 years. However, some specifications of film were not practical and soon disappeared in the market. With the passage of time, it has long been forgotten.

Germany is one of the countries with early development of camera industry. 1928, the German company Fronke Heidecke developed a dual-lens reflex camera using Brownie film, and its performance was quite perfect. The maximum aperture of the photographic lens is 1: 4.5, the focal length is 75 mm, and it is equipped with shutter, and the speed is 1- 1. This is the famous Rolleiflex camera. After the camera was made, the outdated 1 17 film was used. Only six 6x6 cm photos can be taken on one film. It was not until the second year that the 12 film of 6x6 cm image required by the camera was produced, which is the beginning of the 120 film we are using now. 120 film can also take 8 6x9 cm photos, so this film is also manufactured and sold in Germany as model B2-8.

Due to the influence of Rolex cameras, cameras using 120 quickly became popular. In the future, all cameras using 120 film will be collectively referred to as 120 cameras. 120 was originally the serial number of Kodak film in the United States, and the film was used by various countries. When this number is adopted in international standards, it is officially recognized by all countries.

Our country has adopted the names commonly used in the world and has been popularized among the masses. However, some countries still have their own names and traditional customs.