Hacking has multiple meanings and is commonly used to refer to forms of trespass against a computer belonging to another. This brief examines the motives for hacking, in the sense of trespassing against another person's computer. However, this does not match the general criminal definition of hacking-type offences. An intention to commit a serious offence, or to cause harm or inconvenience, lies at the heart of the definition of the more serious computer offences under Australian laws modelled on the Cybercrime Act 2001 (Cwlth). Accessing data alone is an offence where there is an intent to commit a serious offence. The modification or impairment of data is an offence if accompanied by an intention to cause (or recklessness as to causing) harm or inconvenience. Other offences under this model are based on breach of access restrictions in relation to data. Only in Tasmania is the law framed without reference either to the intention of the hacker, or to access restrictions on the computer being hacked.