What is GREY hat techniques in SEO?

Related questions

1. What are SEO tools?
2. What is Google SEO tools?
3. Can Budgett's frog swim?
4. How much should I pay for SEO services?
5. What are the black hat SEO techniques?
6. Do you really need SEO?
7. Do frogs die when you touch them?
8. Is SEO worth the money?
9. Why is SEO so expensive?
10. Is hiring a SEO company worth it?

Tags

1. #redirects
2. #search
3. #keyword
4. #engine
5. #black
6. #swapping
7. #techniques
8. #automation
9. #doorway
10. #increase
11. #content
12. #keywords
13. #practices
14. #invisible
15. #disapproved
16. #using
17. #service
18. #against
19. #rankings
20. #unrelated
21. #terms
22. #pages
23. #range
24. #tactics
25. #going
26. #stuffing