Most compact and SLR cameras use 35mm film. There are some cameras that are designed to use the Advanced Photo System (APS) film. However, they are becoming somewhat obsolete now. The two film formats are not interchangeable, meaning that a camera designed for 35mm film will not work with APS film, and vice versa. Film for APS cameras is slightly smaller then 35mm film and is available in 15, 25 and 40 exposure cassettes. However, some films only come in the longest sizes.
The film comes in a cassette, making it easier to load into the camera. APS has several features designed for convenience. You can choose from three print formats while taking the photo: normal, wide or panoramic. APS film also includes a magnetic strip that stores various information on exposure, such as print format and the number of exposures left on the film. Some APS cameras also have a mid-roll change feature which allows you to change film rolls without losing any exposures. These cameras automatically wind and unwind the film into the cassette for convenience. They start in price from about $50.