Why do people say assault when it can mean assault and battery?

Firstly, we are dealing here with offences against the person. Assault actually splits into 2 categories - a common assault and a battery. These both come under common law. This is important, because it means the actual understanding of the two offences isn't written in an Act. Our understanding comes through cases. To commit an assault, you must have caused another person to apprehend some immediate unlawful force. There are a number of components to understand and we can break these down. Apprehend can be likened to anticipate. The victim does not actually need to be in danger, only fear it. A key case for the is R v Lamb, where the victim was with a friend, and did not actually apprehend the force. Immediate means it must be in the near future. If someone says they will punch you in a month, it is not immediate, so it would not be enough. This is an example of words negating the assault, like in Tuberville v Savage. Unlawful force can cover things like when there is no permission for force to be applied. This comes into the battery explanation. A battery is then that unlawful force. A battery only has to be the slightest of touchings, like a poke, but it must be unwanted. If someone is okay with you touching them, it is not a battery. The mens rea ('guilty mind') for these two crimes is to intend what happened, or to behave recklessly with a chance it would happen and do it anyway.