Types of Film

There are a number of film options out there:

Slide Film
Slide film actually creates a positive image (rather than a negative). This is the film used to create slides for projection. Slide film requires processing known as E6. Because processed slide film doesn't result in actual prints, it is generally cheaper to develop slide film than standard print film. However, this savings is probably negated by the actual cost of slide film, which tends to be a little more expensive. An additional note that should be made regarding slide film is that it is less "forgiving" than other print film. In other words, it is very important that you get the correct exposure when using slide film.

Print (C41)
This is the film we are all familiar with. Color print film requires processing known as C41 (this is the standard film processing done at your local drugstore). This film is used so often and is so common that it isn't too expensive to buy or process.

Black & White Film
Black & white film requires separate processing and printing processes. This type of film is much less widely used now (especially because there are monochromatic C41 films that go through standard color processing, but produce black and white images).

Infrared
Infrared film is an entirely different film. It captures infrared light. This film produces very eerie looking black and white photographs that don't look quite right. (For example the sky is dark and plants are lighter colors)

More photographic film information