Criminal offenses under state and federal laws are generally categorized by the seriousness of the crime as felonies (more serious) or misdemeanors (less serious). Felonies are offenses that generally may result in prison sentences of more than one year, and misdemeanors carry sentences of one year or less. The United States Congress sets the penalties for all federal criminal offenses, and thus decides which criminal offenses are felonies and which are misdemeanors. And the state legislature in each state decides which criminal offenses are felonies and which are misdemeanors under state law.

In Alabama, criminal offenses are classified as either felonies or misdemeanors based on their severity, with felonies being the more serious category. Felonies in Alabama are crimes that can result in imprisonment for more than one year, and they are further divided into different classes (Class A, B, C, and D), with Class A felonies being the most serious. Misdemeanors in Alabama are less serious offenses and are punishable by imprisonment for not more than one year. These are also categorized into classes (Class A, B, and C), with Class A misdemeanors carrying the harshest penalties among misdemeanors. The Alabama state legislature determines the classification of state crimes and their respective penalties. For federal offenses, the classification into felonies and misdemeanors and the determination of penalties are the responsibility of the United States Congress. Federal felonies typically involve more severe penalties, including longer prison sentences, than misdemeanors.