How do I start learning spark?

Related questions

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

Tags

1. #functionality
2. #source
3. #external
4. #second
5. #create
6. #further
7. #apache
8. #moving
9. #before
10. #scala
11. #first
12. #spark
13. #existing
14. #created
15. #shell
16. #different