What is a closed operating system?

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Tags

1. #software
2. #implies
3. #public
4. #change
5. #published
6. #whose
7. #proprietary
8. #neither
9. #freedom
10. #redistribute
11. #closed
12. #computer
13. #means
14. #programs
15. #because
16. #shared
17. #anyone
18. #source