Street photography - street photography are photos that usually contain random incidents in public spaces with the focus normally on people and their behavior - sometimes people may not be present, yet photos can be taken of environments where human activity is evident and can be recorded. 
The photographs don't have to be on the street or in an urban environment, they can be anywhere for example Martin Parr has taken shots on the beach that still come under this category because of the nature of the photos. https://www.martinparr.com/recent-work/
Street photography is almost always candid yet candid photography isn't always street photography.
A candid photograph is when the subject does not pose for the camera.