What's the difference between HD and Blu Ray?

Related questions

1. Will Blu Ray upscaled to 4k?
2. Is there anything better than Blu Ray?
3. Will 4k play on Blu Ray?
4. Is Bluray better?
5. Does Blu Ray look better on 4k TV?
6. Which is better HDrip or Web DL?
7. Can you use a regular Blu Ray player on a 4k TV?
8. Are blu rays worth it?
9. Which is better Blu Ray or HD?
10. What quality is SD?

Tags

1. #contrast
2. #store
3. #current
4. #single
5. #difference
6. #information
7. #layer
8. #while
9. #between
10. #optical
11. #major
12. #capacity