How does Google PageSpeed work?

Related questions

1. What is domain lookup time?
2. What is performance grade in pingdom?
3. What is a good first byte time?
4. What is fully loaded page?
5. Does Page Speed affect SEO?
6. What is mobile speed score?
7. How does pingdom work?
8. What causes long TTFB?
9. What is a good Google Page Speed score?
10. What is request GTmetrix?

Tags

1. #automatically
2. #practices
3. #servers
4. #speed
5. #across
6. #users
7. #rewrites
8. #applying
9. #online
10. #serves
11. #globe
12. #pagespeed
13. #performance
14. #content
15. #pages
16. #service
17. #fetches
18. #google
19. #loading