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 Michigan, burglary is defined under the Michigan Penal Code as breaking and entering or entering without breaking with the intent to commit a felony or a larceny therein. This is covered under MCL 750.110 'Breaking and entering; buildings, tents, boats, railroad cars'. The statute does not require actual theft or felony to occur; the intent to commit a felony or theft is sufficient. Michigan law distinguishes between different types of structures, such as dwellings, businesses, and other types of buildings, with the burglary of a dwelling often being treated more severely. The state also recognizes home invasion as a separate offense, which is similar to burglary but specifically involves entering a dwelling. Home invasion is categorized into three degrees in Michigan, with the first degree being the most serious and involving either the presence of a dangerous weapon or an assault. The second and third degrees involve lesser circumstances but still carry significant penalties. The specific charges and penalties for burglary or home invasion can vary based on the circumstances of the crime, such as the presence of occupants, the time of day, and whether any other crimes were committed during the unlawful entry.