Burglary is generally the unlawful entry of a building or structure to commit a felony criminal offense (crime), theft, or assault. The definition of burglary varies from state to state (and in the federal system), and some states have different degrees of severity of the burglary offense—depending on the nature of the unlawful entry (type of building or structure), the intended purpose, and the illegal action taken by the defendant once inside the building or structure. In some states, breaking into an automobile, a coin-operated machine, or an ATM (automated teller machine) with the intent to commit a theft may also constitute the crime of burglary.

In Connecticut, burglary is defined under state statutes as the unlawful entry into a building or structure with the intent to commit a crime therein, typically theft or a felony. Connecticut law recognizes different degrees of burglary, which are classified based on factors such as the time of the offense, whether the building is a dwelling, whether the offender is armed, and whether the burglary results in physical injury to any person. For example, Connecticut General Statutes Section 53a-101 defines Burglary in the first degree, which is a Class B felony, as entering or remaining unlawfully in a building with intent to commit a crime therein and either being armed with explosives or a deadly weapon, or causing injury to anyone during the act. Burglary in the second and third degrees are defined in Sections 53a-102 and 53a-103, respectively, with varying levels of severity and corresponding penalties. The state does not limit the definition of burglary to buildings alone; it can also apply to illegal entry into other structures, such as an automobile, if the intent is to commit a crime.