What is the difference between SEM and PPC?

Related questions

1. Does SEO affect PPC?
2. Can I advertise on Google for free?
3. Can you pay Google for SEO?
4. What is a PPC budget?
5. Do PPC ads work?
6. Why is PPC so important?
7. Is PPC part of SEO?
8. What is PPC machine?
9. Why is PPC important?
10. What is CPM in PPC?

Tags

1. #difference
2. #thing
3. #clicks
4. #charged
5. #latter
6. #engines
7. #where
8. #based
9. #meant
10. #affiliate
11. #click
12. #display
13. #advertising
14. #someone
15. #former
16. #between
17. #common
18. #stands
19. #search