Photography is employed in many fields of science, manufacturing (e.g., photolithography), and business, as well as its more direct uses for art, film and video production, recreational purposes, hobby, and mass communication.
Photography may be used in Surveillance
Unfortunately, there is a widespread, continuing pattern of Law Enforcement Agency officers ordering people to stop taking photographs from public places, and harassing, detaining and arresting those who fail to comply.
When you are on private property, the property owner may set rules about the taking of photographs. If you disobey the property owner's rules, they can order you off their property (and have you arrested for trespassing if you do not comply).