What is Facebook secret conversation?

Related questions

1. Why is it 12pm and not 12am?
2. How do I turn on PM in Facebook?
3. How many types of maintenance are there?
4. What does SKL and SML means?
5. What is PM and AM stand for?
6. What is DM slang?
7. What are the classification of maintenance?
8. What is PM Facebook?
9. How do I see private messages on Facebook?
10. What is an example of preventive maintenance?

Tags

1. #secret
2. #choose
3. #messaging
4. #screenshot
5. #encrypted
6. #anyone
7. #including
8. #person
9. #which
10. #conversation
11. #share
12. #messenger
13. #others
14. #could
15. #intended
16. #other
17. #messages
18. #means