What is the purpose of the Uniqueidentifier data type?

Related questions

1. What is GUID used for?
2. Should I use GUID as primary key?
3. What is the length of GUID?
4. How big is a GUID?
5. What is Uniqueidentifier datatype in SQL Server?
6. What are the chances of a GUID collision?
7. Is GUID really unique?
8. How many GUID combinations are there?
9. What are the odds of a GUID repeating?
10. What is GUID value?

Tags

1. #known
2. #primary
3. #universally
4. #other
5. #values
6. #column
7. #uniquely
8. #identifier
9. #often
10. #uniqueidentifier
11. #identify
12. #storage
13. #unique