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 South Dakota, assault is defined under SDCL 22-18-1 as an attempt to cause bodily injury to another, or intentionally causing bodily injury to another, or intentionally making another person reasonably fear imminent bodily harm. The state differentiates between simple assault and aggravated assault. Simple assault is generally a misdemeanor, but it can be a felony under certain circumstances, such as when committed against a law enforcement officer, in a domestic abuse situation, or when the victim is a minor. Aggravated assault, as per SDCL 22-18-1.1, occurs when a person attempts to cause serious bodily injury to another, or intentionally causes such injury under circumstances manifesting extreme indifference to the value of human life. Using a deadly weapon to commit an assault would typically elevate the crime to aggravated assault, which is a felony in South Dakota. The specific classification and penalties for assault and aggravated assault depend on various factors, including the severity of the injury, the status of the victim, and the intent of the perpetrator.