What is difference between PubMed and Pubmed Central?

Related questions

1. How many articles are in PubMed?
2. Is PubMed and Medline the same?
3. Are articles on PubMed peer reviewed?
4. What are PubMed articles?
5. Why is PubMed a good database?
6. Are PMC articles peer reviewed?
7. Is PubMed legitimate?
8. Is PubMed same as Medline?
9. Is PubMed Medline?
10. Are PubMed articles peer reviewed?

Tags

1. #millions
2. #articles
3. #provided
4. #index
5. #library
6. #documents
7. #biomedical
8. #subset
9. #medicine
10. #contains
11. #institutes
12. #national
13. #health
14. #central
15. #pubmed