This weekend, the UK officially enters Autumn as daylight savings time ends and the clocks return to Greenwich Mean Time (GMT).

The twice-yearly change has been in operation in the UK for more than a century - yet the transition continues to catch thousands of people out every year.

It does mean an extra hour in bed, but can leave some people feeling a little bit out of sync.

Here is everything you need to know about the clocks falling back.

READ MORE: Everything you need to know about GlasGLOW at the Botanics

Why do we put the clocks back?

I'm glad you asked.

The idea of daylight saving time was first mooted in the 18th century by American inventor Benjamin Franklin, but was not considered in Britain until 1907.

London builder William Willett complained of a “waste of daylight” in a pamphlet issued in 1907, tabling radical plans to advance the clocks by 20 minutes on each of the four Sundays in April and reversing it on the same days in September.

Willett’s proposals were initially shot down, but support steadily grew partially thanks to his vigorous campaigning.

Willett succumbed to influenza in 1915, a year before British Summer Time (BST) was introduced.

The Summer Time Act was put forward as a way to save coal during the First World War, but was quickly adopted as a permanent measure.

It became more widespread across the rest of the world in the 1970s due to the energy crisis.

When do the clocks go back?

The clocks officially change at 02:00 am on Sunday morning.

At that time, all clocks in the UK are moved back by an hour to 01:00 am.

Glasgow Times:

That means an extra hour in bed - or an extra hour out drinking if you prefer.

Most smartphones should automatically reset, however manual clocks, such as those on the wall and bedside alarm clocks will probably have to be positioned at the right time.

We have no idea how individual items like ovens, thermostats or any other devices can be properly set - please consult someone with a masters in electrical engineering before us.

READ MORE: Fire bosses coordinate for Bonfire Night trouble

When do they change again?

GMT ends in the spring when we go back to BST.

In 2020, GMT ends on Sunday, March 29 to mark the ‘official’ start of summer.

We have no idea what the forecast is for that day, but we are going to guess it will rain.