Waterproof: This is your best option for inkjet printing. A waterproof film has a special coating on it that retains the ink and allows the film to hold more ink then a standard film. More ink equals a darker image. This coating also sucks the ink into the center of the film and holds it there so it stays darker longer, doesn’t scratch as easy and resists water spills.
Standard Inkjet: Older styles of Epson printers can take standard inkjet film. Some printers try to use this film because it is cheaper, however unless you have a specific style of printer that the film works good with, it will be hard to get a good looking dense positive with standard film on any of the newer printers.
Laser Film: Specifically for laser printers, this is a thicker film with a haze. It’s built to resist heat and minimize shrinking.