In 1951, the United Nations defined a refugee as:
"A person who, owing to a well-founded fear of being persecuted for reasons of race, religion, nationality, membership of a particular social group or political opinion, is outside the country of his/her origin, and is unwilling or ... unable to return to it."
This international agreement has been signed by 107 countries around the world, including the United Kingdom. But it excludes many other people who have been forced from their homes. Millions of people escape from persecution but do not leave their own country. Others are forced to leave because of environmental degradation and may be just as in need of support as those who fall under the UN definition. In a sense, anyone who has been forced to flee is a refugee.
To find out more, download the Refugees factsheet.