Street photography is an approach to photography rather than a location, although the streets are the usual place that it happens.
The plethora of equipment (tripods, lenses, filters, lights etc) associated with "serious" photography is left at home, or better still in the camera store. It’s just too heavy and bulky to cart around, takes way too long to set up and by the time it is set up the moment is gone.
Street photography is photography from the hip, the rules of photograph, the f stops, the shutter speeds, the rule of thirds etc are left in their dust jackets on Amazon shelves. By the time all the technical considerations are taken into account, the birdie is in another country.
It is just the camera and the photographer with their enthusiasm, intuition and open mind.
Street photographers are optimists, for them the glass is always half full. They go out on a photo shoot with no plan in mind secure in the knowledge that a subject, a situation, a scene will present itself. All they have to have is the presence of mind to capture it when it does.
Street photographers see the usual, the every day with fresh eyes. The reflection in a rain puddle, the colours in a crowd, the balance of a negative space. Their minds are open to all the stimuli that they see and they curse the days when they leave their camera at home.
Street photographers are not only on the streets, they are at weddings, school concerts, next to you on the train. They look a lot like tourists, it’s their favourite cover but they are one without the big flash. It was left at home, the available light will do.
Street photography is, what all photography is, a snap shot. What shines through is the photographer, his/her interpretation of the scene, what they see in the situation, their reaction to the stimuli, the art they see in the every day.