Street photography is a type of photography that features subjects in candid situations within public places. Street photographs are mirror images of society and show ‘unmanipulated’ images. Street photography can also be known as candid photography. Street photography can focus on people and their behaviour in public.
A great example is Bruce Gilden. He is best known for his candid close-up photographs on the streets of New York whilst using a flashgun to capture initial reactions of people in public. Here is a video showing his work.