Burglary, also called breaking and entering, is illegally going into a building or area in order to commit a crime, usually theft. Someone who does burglary is called a burglar. To commit burglary is to burgle or to burglarize. Burglaries can happen at any time or any place. The word burglar comes from the Old English words burg (house) and laron (thief). 
The definition of burglary, and the punishment for burglary, depends on the country or state.