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.

A defendant generally commits the offense of burglary of a building or habitation (1) by entering a private habitation or any part of a building that was not open to the public, (2) without the consent of the owner, and (3) with the intent to commit a felony, theft, or assault.

A defendant may also commit the offense of burglary of a building or habitation by entering with consent, but remaining hidden with the intent to commit a felony, theft, or assault—or entering with consent and attempting to commit a felony, theft, or assault, or actually committing a felony, theft, or assault.

Some states make a distinction between burglary of a habitation (a place used for overnight accommodations) and burglary of a building that is not a habitation (home). Burglary of a habitation is usually treated as a more serious offense with greater penalties.

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 assault. Connecticut law distinguishes between different degrees of burglary based on factors such as the type of building entered, whether it is a dwelling, and the circumstances of the entry. For example, burglary in the first degree, which is considered the most serious form, involves entering or remaining unlawfully in a dwelling at night with the intent to commit a crime, and it may involve the use or threat of use of a dangerous instrument. Burglary in the second degree may involve entering a dwelling during the daytime or a building that is not a dwelling, with similar intent. Burglary in the third degree generally involves entering or remaining in a building with intent to commit a crime. The severity of the charge and the associated penalties increase if the burglary involves a dwelling or if the offender is armed or threatens to use a weapon. Connecticut law also covers burglary with explosives, which is a separate offense. The specific statutes that outline burglary offenses in Connecticut are found in Chapter 952 of the Connecticut General Statutes, Sections 53a-101 to 53a-108.