Despite being a single continent, Europe has different time zones, which includes the hours of sunshine that each country usually has during the year. Within the five time zones that Europe, the United Kingdom and Ireland have, they are in the so-called Western European Time or WET, which coincides with Greenwich Mean Time or Coordinated Universal Time (UTC). All countries that are in the WET zone advance the time in summer (UTC + 1), except Iceland. You have all the information in: «Time change and time system in the UK«.
You have all the information in: "Time change and time system in the UK".