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 Virginia, burglary is defined under Virginia Code § 18.2-89 as the act of breaking and entering the dwelling house of another in the nighttime with the intent to commit a felony or any larceny (theft) therein. This traditional definition has been expanded by § 18.2-90 to include entering without breaking, breaking without entering, or entering and hiding, with the same intent, during the daytime or nighttime. Virginia law distinguishes between burglary of a habitation and other buildings. Burglary of a habitation, which is considered a more serious offense, is typically charged as a Class 3 felony, while burglary of other buildings may be charged differently depending on the circumstances, such as whether it was armed burglary or if there was intent to commit assault and battery or other felonies. The penalties for burglary can be severe, including imprisonment and fines. It's important to note that Virginia does not require the actual commission of the intended crime for a burglary charge; the intent to commit a crime is sufficient.