The United Kingdom has several public holiday across the year. Some are observed throughout the UK, others by certain countries therein. These holidays are commonly known as bank holidays as traditionally they were days that banks would shut meaning no other businesses could operate.
For example today, Monday the 26th May 2008, is a public holiday in the UK being the last Monday in May also known as Spring Bank Holiday. Most of the UK will have time off work on this day, although it is not a legal requirement. Emergency services and other such business that need to operate all the time would obviously continue to work on public holidays but may receive extra pay for doing so.
Current bank holidays were passed by the Banking and Financial Dealings Act 1971. The current number of bank holidays in a year total 8 in England and Wales, 9 in Scotland and 10 in Northern Ireland. The main reason England and Wales have less is that currently they do not have a public holiday allocated to the feast days of their respective patron saints whereas Scotland and Ireland do.
This is something that is possibly going to change in the near future especially as the UK has a notably smaller number of public holidays than other European countries.