Most organs can be donated by deceased donors while living donors can donate their kidneys and liver.
When people sign up to the organ donor register in the UK they receive a donor card which most people keep on them.
According to the organ donation NHS website, on average around three people die every day waiting for a suitable organ.
Around 6,500 people across the UK are waiting for an organ transplant and only around 5,000 people each year die in circumstances where they can donate their organs.
The NHS organ donation website has a range of information on how to register, what happens when you do, the different types of transplants, restrictions and the difference it can make.
It also has patient stories on people who have given an organ and been a recipient.
For more information or to register visit call 0300 123 23 23 or visit organdonation.nhs.uk.