A more thorough explanation:

A court-martial is a legal proceeding where members of the military are tried for breaking military laws. There are three types of courts-martial: general, special, and summary. The jurisdiction of the court-martial depends on the seriousness of the offense and the allowable penalty under the Uniform Code of Military Justice (UCMJ).

Courts-martial have a limited jurisdiction and can only try members of the armed forces. There are three prerequisites for jurisdiction to vest: jurisdiction over the offense, personal jurisdiction over the accused, and a properly convened and composed court-martial. The UCMJ and the Rules for Courts-Martial specify who may convene a court-martial.

• General Courts-Martial: These courts have jurisdiction to try any offense punishable by the UCMJ. They consist of a military judge and at least five members (jurors) or only a military judge if the accused requests it in writing. General courts-martial can adjudge punishment ranging from a dishonorable discharge to life imprisonment or death by lethal injection.
• Special Courts-Martial: These courts have jurisdiction to try noncapital offenses punishable by the UCMJ and, under certain regulations, capital offenses. They consist of at least three members or a military judge and at least three members. Special courts-martial can adjudge incarceration up to six months.
• Summary Courts-Martial: These courts have jurisdiction to try noncapital offenses punishable by the UCMJ, except for officers, cadets, aviation cadets, and midshipmen. They consist of one commissioned officer and can only impose a maximum of one month's confinement.

The accused has the right to be represented by counsel before a general or special court-martial. They can choose to be represented by civilian counsel or military counsel if reasonably available. All military defense counsel are licensed attorneys who have received specialized training in military law.

An example of a court-martial is when a soldier is tried for desertion. If found guilty, they could face a dishonorable discharge or even imprisonment. The type of court-martial would depend on the seriousness of the offense and the allowable penalty under the UCMJ.