GET ready for the nights to draw in, temperatures to drop and Christmas to be here in the blink of an eye. 

The clocks go back at 2am this Sunday (the last Sunday in October), resulting in an extra hour. 

When the clocks go back, the UK is on Greenwich Mean Time (GMT).

When they go forward - at 1am on the last Sunday in March - it is called British Summer Time (BST), sometimes called Daylight Saving Time.

But why do we do this? 

William Willett, who died of influenza at the age of 58, was a tireless promoter of British Summer Time.

This was to make use of the daytime and prevent wasting it first thing in the morning during the summer.

He wrote a leaflet, The Waste of Daylight, prompting the idea of clocks moving backwards in autumn and forwards in spring.

His concept became law in 1916, a year after his death.

Willett is a great-great-grandfather of Coldplay singer Chris Martin.

The maximum 16 hours and 50 minutes of sunlight - on the longest day in June (the summer solstice) - dwindles to just seven hours and 40 minutes in December (the winter solstice).