How does ad blocker work?

Related questions

1. Should I use an ad blocker?
2. Is it legal to use AdBlock?
3. Is uBlock better than AdBlock?
4. Are ad blockers any good?
5. How does an ad blocker work?
6. Why is Adblock disabled in Chrome?
7. Is AdBlock free for Chrome?
8. How does AdBlock make money?
9. What is browser assistant?
10. Why does my Google Chrome keep popping up ads?

Tags

1. #called
2. #visit
3. #injects
4. #means
5. #blocked
6. #relies
7. #block
8. #allow
9. #whitelisted
10. #instead
11. #appear
12. #blockers
13. #adblock
14. #pages
15. #stylesheet
16. #filter
17. #every
18. #rules
19. #sites