A more thorough explanation:

The Blockburger test is a legal test used in criminal law to determine whether a defendant can be punished separately for convictions on two charges or prosecuted later on a different charge after being convicted or acquitted on a charge involving the same incident.

The test compares two charges to see if each contains at least one element that the other does not. This is done to ensure that a defendant is not punished twice for the same offense, which is prohibited by the Double Jeopardy Clause of the Fifth Amendment to the United States Constitution.

For example, if a defendant is charged with both assault and battery, the Blockburger test would be used to determine whether the defendant can be punished for both offenses. If assault and battery have different elements, such as assault requiring an attempt to cause bodily harm and battery requiring actual bodily harm, then the defendant can be punished for both offenses. However, if the elements of assault and battery are the same, then the defendant can only be punished for one of the offenses.

The Blockburger test was established in the case of Blockburger v. U.S. in 1932 and is also known as the same-elements test or actual-evidence test.