The crime of assault varies from state to state (and under federal law), but is generally defined as intentionally putting another person in reasonable apprehension or fear of an imminent (immediate) harmful or offensive contact. The crime of assault may be committed even if there is no physical contact, as the criminal physical contact constitutes the separate crime of battery.

The crime of assault with a deadly weapon (also known as aggravated assault) occurs when someone uses a deadly weapon (gun, knife, club, tire iron, brass knuckles, etc.) during an assault.

In Massachusetts, assault is defined under Massachusetts General Laws Chapter 265, Section 13A. An individual commits assault by either attempting to use physical force against another or by demonstrating an intention to use immediate force against another, which causes the victim to fear an imminent battery. The crime of assault does not require physical contact, distinguishing it from battery, which involves actual physical contact. Assault with a deadly weapon, also known as aggravated assault, is a more serious offense under Massachusetts law. It occurs when an individual commits an assault using a deadly weapon, such as a firearm, knife, or any object that could cause serious harm or death. This type of assault is addressed under Massachusetts General Laws Chapter 265, Section 15B, and carries more severe penalties due to the potential for greater harm. Penalties for assault and aggravated assault in Massachusetts vary based on the circumstances of the crime and the harm caused, and can include fines, imprisonment, or both.