Can you identify and describe the limits of executive power, in relation the UK government?

UK government

1. Can you identify and describe what is meant by the term executive power? What is the executive in the UK and how is it composed? What is the role of the executive, in the UK?
2. Can you identify and describe the limits of executive power, in relation the UK government?
3. What are some examples of abuses, by the UK or foreign governments, of executive power?