IT law is the collection of laws which regulate the information infrastructure (networks etc), the nature of information carried and stored and the uses that can be made of such information.
Users are regulated by intellectual property rights. Copyright requires permission to use any manifestation of an original work, and each permission and manifestation operates separately from the others, thus one has screenplay rights and music rights on a film distinct from the film rights as such, and Internet access rights are separate from performance rights in a cinema or by broadcast. Permission is given via collective licences or directly subject to very limited exceptions.
The infrastructure is regulated by publishing laws such as libel, media ownership rights and rules of balanced reporting. There are also security and interception laws.
Rules of access include Data Protection and Freedom of Information law and the Human Rights act 2000 and also the Computer Misuse Act 1990. Access rules also cover exclusion of pornography or of libellous material. With libel there is an obligation to remove material when told of a libel, but this is controversial as this accusation might not be held valid in court and yet the material would have been absent for a long time.
In short, this is a topic created by the subject matter on which the law acts, and a wide-ranging set of laws act on the infrastructure and contents of IT systems.