The UK operates on a time-zone called Greenwich meantime (GMT), which is in keeping with Western European Time. The only other country in Europe to share our time zone is Portugal; the rest of Europe uses either Central European Time or Eastern European Time.
GMT
GMT is UTC (Coordinated Universal Time) + 0 or during summer when we switch to Western European Summer Time (more commonly known in the UK as 'daylight saving time') it is UTC + 1.
Greenwich Meantime took its name from the Royal Observatory in Greenwich London, and is rooted in Britain’s maritime history. British sailors always took a watch with them that was set to GMT, in order to calculate their Longitude from the Greenwich meridian. This is why the UK is still to this day the home of time zero.
Daylight Saving Time
Daylight saving time was introduced in the UK back when it was an industrial nation to provide enough light in the mornings to help people get to work.
Twice a year everyone in the UK has to change their clocks, putting them one hour forward in the summer and one hour backwards in the winter. It is regarded by most Brits as a real inconvenience and many people would like to see the whole thing abolished altogether. Many people argue that putting the clocks back deprives the UK of precious light in the winter evenings when it gets dark as early as 4 p.m. and that the country would be better off just staying on UTC + 1 all year round. This is a debate that you will discover the UK indulges in twice a year but never really does anything about.
Quick reference guide
City Hours ahead of UK
Paris, Madrid, Rome - 1
Athens, Helsinki - 2
Moscow - 3
Tashkent - 5
Delhi/Mumbai - 5.5
Bangkok - 7
Hong Kong/Beijing - 8
Tokyo - 9
Sydney - 10
Wellington - 12
City Hours behind UK
Honolulu - 10
L.A./San Francisco - 9
Denver - 7
Chicago/Dallas - 6
NY/Miami - 5
La Paz - 4
Buenos Aires - 3
USEFUL WORDS
standard time = the official time of a country or an area
local time = the time of day in the particular part of the world that you are talking about
Greenwich Mean Time (GMT) = the time at Greenwich in England, used for calculating the time everywhere in the world = Universal Time
British Summer Time (BST) = daylight saving time = the period between March & October when some countries put their clocks forward one hour, so that it is light for an extra hour in the evening
Central European Time (CET) = the time used in central and part of western Europe, which is one hour later than GMT
USEFUL EXPRESSIONS
Asking for Times
‘What’s the time?’
‘What time is our meeting tomorrow?’
‘When does the programme start?’
‘Excuse me. What time does the next train leave?’
‘Have you got any idea what time the film starts tonight?’
’When is your mother arriving?’
‘What’s the time difference between England and Germany?’
‘Germany is one hour ahead of England’
‘England is an hour behind Germany’
Giving Times
‘It’s ten past four / four ten’
‘At 10.30 / half past ten’
‘It’s at eleven o’clock in my office’
‘Twenty-three minutes past two’
‘In the morning / afternoon / evening’
‘At night’
‘Today / tomorrow / yesterday’
‘At midnight / noon’
Time Idioms
Long time no see = we haven’t met for ages
Tomorrow is another day = forget about the problems of today for now
It’s only a matter of time = things will happen eventually
We decided on the spur of the moment = we decided quickly, there and then
There’s no time like the present = don’t wait – do it now!
It’s very cold for this time of year = it’s colder than it usually is at this time of the year
Geography 
