Why do goalkeepers wear helmets?

Related questions

1. Is Petr Cech a triplet?
2. Why do Arsenal and Tottenham hate each other?
3. Why is it called the Kop?
4. Who has more fans Chelsea or Arsenal?
5. Can Arsenal increase stadium capacity?
6. What's the richest football club in the world?
7. Is Arsenal a real place in London?
8. Did Petr Cech retire?
9. What does the 3252 mean?
10. Has Arsenal won Europa?

Tags

1. #games
2. #goalkeeper
3. #wanted
4. #protection
5. #goalkeepers
6. #forced
7. #should
8. #skull
9. #typical
10. #rugby
11. #protecting
12. #order
13. #helmet
14. #wears
15. #concussions
16. #headgear
17. #playing