When do the clocks change and why?

Last updated at 07:22
ClockGetty Images

It's that time of year again when we change the clocks forward.

This year it's happening on Sunday 27 March, but as the actual time change is during the night, you'll probably be fast asleep in bed when it happens!

When the clocks change like this, we are moving from what is called Greenwich Mean Time (GMT) to British Summer Time (BST) - also known as Daylight Saving Time (DST) or GMT+1.

Even though we get an hour less in bed, the benefit is that we get an extra hour of daylight in the evenings so it won't go dark so quickly after school!

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Thankfully most smart phones, computers, and other devices connected to the internet, normally update the time automatically.

But, if you have a watch or clock that isn't digital, don't forget to check if you need to manually reset the time.

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Ricky looked at ways to spend an extra hour in bed when the clocks go backwards in the Autumn (October 2014)
Why do we change the clocks?

An American politician and inventor called Benjamin Franklin first came up with the idea while in Paris in 1784.

He suggested that if people got up earlier, when it was lighter, then it would save on candles.

Benjamin FranklinGetty Images
Benjamin Franklin, who first came up with the idea of moving the clocks according to daylight

But it arrived in the UK after Coldplay singer Chris Martin's great-great-grandfather, a builder called William Willett, thought it was a good idea too.

In 1907, he published a leaflet called The Waste of Daylight, encouraging people to get out of bed earlier.

Chris Martin
Coldplay singer Chris Martin's great-great-grandfather is responsible for introducing the idea of moving the clocks in the UK

Willett was a keen golfer and he got cross when his games would be cut short because the sun went down and there wasn't enough light to carry on playing.

When did we start changing our clocks?

The idea of moving the clocks forwards and backwards was discussed by the government in 1908, but many people didn't like it so it wasn't made a law.

Willett spent his life trying to convince people that it was a good idea, but it was only introduced in the UK in 1916 - a year after he died.

Man playing golfGetty Images
William Willett used to get cross when it got too dark for him to carry on playing golf

It was actually first introduced by the Germans in World World One, just before the UK did it.

During World War Two, the UK used what was called British Double Summer Time (BDST), when the clocks were ahead by an extra hour during the summer. But this didn't last for very long.

William WillettGetty Images
William Willett unfortunately died before he could see his idea introduced

Now, the UK's clocks always go back by one hour on the last Sunday in October and forward by one hour on the last Sunday in March.

Moving clocks like this is now done in some countries across the world, but many still don't do this.

What do people think of it?

Lots of people have different opinions about whether we should change our clocks like this.

ClockGetty Images
Not everyone thinks that changing the clocks the way that we do is a good idea

Some think having BST is a good thing because it saves energy, by making better use of natural daylight, and helps to reduce traffic accidents.

Others don't like it because they argue that it doesn't actually save any energy, and it can make it darker when children are going to school in the morning, which can be dangerous.

They also think changing clocks and time in this way isn't very good for our health.