Many people haven't heard of the term street photography, but it generally means photographs that are taken in public places. This means locations such as streets, parks, malls, beaches and public events, etc. The photos are usually everyday life photos. It isn't really a commercial type of photography, but many interesting street photography magazines and books are sold every year. In a way it is similar to photojournalism as it often captures a specific human moment, but there is usually no historical or social significance to the photo other than the photographer's interest. Photos of children skipping in a park or a couple kissing at a train station are examples of street photography.
The photos don't usually concern themselves with who the subjects are, but what they are doing. You often get photos with interesting things going on in the background that you never noticed when you took the photo. A good speed film to use for this photography is ISO 400. Digital cameras are ideal for street photography as you can take dozens a day without having to worry about film. Feel free to take photos of anything that interests you.