Taking photos of people when they have no idea that you’re doing it is called candid photography. One of the beauties of photography is being able to catch someone in the act. It adds life to your pictures.
Candid photography is all about understanding and capture unplanned moments of someone’s emotions, be it cheerfulness or tears. Photographers will look far and wide, over the crowds and through the landscape looking for that one in a million shot. Having a camera ready is essential. Taking shots of friends and family can be tough because they are most likely aware of you and what you’re doing and therefore they become distracted.
If you want to get good shots of your friends, the focus has to be on something else other than the camera. Get them talking about something that they like. Your goal for doing this is to try to get them to forget you’re carrying a camera. In getting them to forget, they are more likely to act naturally.