What is the meaning of actus reus and mens rea?

Actus reus and mens rea are latin terms used in Criminal Law in England and Wales. Actus reus refers to the, "guilty act" of a crime, and mens rea refers to the, "guilty mind" of a crime. For example, if the crime is rape, the actus reus is the insertion of a human penis into a human orifice, and the mens rea is the intention to do so or lack of reasonable belief that the victim was consenting to the penetration.