How is Hadoop different from spark?

Related questions

1. Why spark is used in Hadoop?
2. How do I start learning spark?
3. Do I need Scala for spark?
4. What is faster than Apache spark?
5. What is spark language used for?
6. How long does it take to learn spark?
7. What is spark in Hadoop?
8. Why should I learn spark?
9. Why do we need spark?

Tags

1. #mapreduce
2. #which
3. #based
4. #memory
5. #strictly
6. #entire
7. #filesystem
8. #spark
9. #doesn
10. #example
11. #distributed
12. #whereas
13. #ecosystem
14. #computing
15. #processing
16. #competes
17. #framework
18. #cluster
19. #means
20. #hadoop