What is the difference between a princess and a princess royal?

Related questions

1. What did Princess Margaret die off?
2. Does Princess Margaret marry Peter Townsend?
3. Where did Princess Margaret marry?
4. Why is Camilla a duchess?
5. Who is older Prince Charles or Princess Anne?
6. What happened to Queen Anne's husband?
7. What happens if Charles dies before the Queen?
8. How old was Queen Elizabeth when she had her last child?
9. Who raised Anne Boleyn's daughter Elizabeth?
10. Can there ever be a king of England?

Tags

1. #eldest
2. #automatically
3. #daughter
4. #never
5. #there
6. #current
7. #customarily
8. #elizabeth
9. #queen
10. #monarch
11. #substantive
12. #princesses
13. #princess
14. #british
15. #awarded
16. #title
17. #royal
18. #seven
19. #possession