The difference between weather and climate
It is important to understand that there is a difference between weather and climate. Weather describes the variations which occur in the atmosphere on a daily basis, whereas climate is the typical (or average) weather experienced at a place over a longer period of time (typically 30 years). To put it another way, if you could choose to live anywhere in the world, the climate of a country might determine where you choose to live (colder Canada or hotter Indonesia, say). Once there, the weather determines your daily choices: Sun cream or umbrella? BBQ in the garden or a party indoors?
We can divide the world into different climatic zones. Typically the climate is cooler the further you move from the equator.
An example: Snowdonia
North Wales has a distinct climate, a result of its latitude, its position on the western edge of Europe and strongly influenced by its closeness to the sea (a maritime climate). The region's climate is typified by cloudy, wet, windy but relatively mild conditions. In Snowdonia, this is a modified by the presence of mountains, which can experience harsh winter conditions.
However, this does not mean the weather in Snowdonia never changes. Just look at these two photographs of the area:
The photo on the left was taken on the 4th April 2012, the one on the right a day later. This clearly illustrates that weather is short-term, climate is long-term.
The British climate
The British Isles are within the climatic zone known as 'temperate', a zone characterized by cold winters and mild summers. The climate of Britain is quite cool, and is described as 'equable', which means 'lack of extremes'. The summers are relatively cool, winters are generally mild and there is frequent rain.
Britain's weather is quite changeable, and does not usually receive long periods of hot or cold weather, or long periods of prolonged drought or rainfall.
There are many factors that affect climate, which are explored in a separate tutorial.