Yes, TB is contagious. Let's say you are in a crowded resteraunt sitting at the table next to a person who has TB. Chances are, you don't know they have it and they don't even know they have it (See "Symptoms")! If they accidently cough on you, and you breathe in that air, you will probably become infected with TB. It's spread that easily. TB is a disease of the lungs, so anytime someone with TB breathes near you, coughs near you, speaks near you or sneezes near you, the air around you is infected with TB. By letting coughs, sneezes, sounds, or breath come out of their mouth, they are sending their germs into the air and near you.
