An Executor is the person you name in your Will to carry out the terms of your Will and should be chosen with extreme care. One Executor is sufficient but two is more ideal should anything happen to one or the other.
Executors can benefit in the Will (ie. receive property, money or a gift). They must be over 18 years of age. Before making your Will you should consult with the person you are planning to nominate as your Executor to see if they are happy to take on the role.