What is the difference between subdomain and subdirectory?

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Tags

1. #subdirectories
2. #subdirectory
3. #contained
4. #basically
5. #yourdomain
6. #files
7. #other
8. #domain
9. #folder
10. #created
11. #contains
12. #within
13. #alias
14. #subdirectory1
15. #address
16. #another
17. #subdomain