What are triggers in GTM?

Related questions

1. Why network models are divided into layers?
2. Is Google Tag Manager the same as Google Analytics?
3. What is layering as used in DTP?
4. What is GTM Dom?
5. What are the layers?
6. How do you use Google tags?
7. What is Dom ready?
8. What is GTM tracking?
9. What is a Google Tag Manager ID?
10. What is Google Tag Manager and its benefits?

Tags

1. #specified
2. #submissions
3. #manager
4. #google
5. #events
6. #button
7. #triggers
8. #event
9. #response
10. #about
11. #tells
12. #trigger
13. #clicks
14. #listens
15. #detected
16. #mobile
17. #views
18. #types
19. #certain