The UK has three different legal systems; one for England & Wales, one for Scotland, and one for Northern Ireland. All three are common law systems, and for copyright they have had to incorporate the Berne Convention and various European Union directives which makes the copyright law quite similar. But we do have separate Creative Commons licenses for England & Wales and for Scotland for example. For an (inaccurate) American comparison the three legal systems are like state law, with the EU as Federal law.
The UK has Fair Dealing rather than Fair Use. Fair Dealing is much, much weaker than Fair Use from a Free Culture point of view. There aren’t that many rights under Fair Dealing for DRM to restrict.
Fair Use and Fair Dealing are both examples of exceptions to copyright. Exceptions to copyright are allowed by the Berne Convention:
http://www.wipo.int/treaties/en/ip/berne/trtdocs_wo001.html#P140_25350
Fair Use is a generic exception, where use has to pass a four-point test to be allowed:
http://en.wikipedia.org/wiki/Fair_use#Fair_use_under_United_States_law
Fair Dealing is a series of specific exceptions, where use has to be explicitly mentioned in law to be allowed:
http://en.wikipedia.org/wiki/Fair_dealing
Fair Dealing in the UK has been reduced over the years to the point where it now just covers copying for academic research and time shifting. Oh, and review and criticism. We have no right of personal copying or format shifting:
http://en.wikipedia.org/wiki/Copyright_law_of_the_United_Kingdom#Fair_dealing_and_other_exceptions
We are hopefully getting some more Fair Use-like exceptions for parody and transformative use, as well as format shifting, as a result of the Gowers Review of “Intellectual Property”:
So that’s the state of play for copyright exceptions in the UK.
(Revised from a post to FC-discuss.)