Here's a place you can start: Hadoop For Dummies. . IBM (my employer) is providing it. Once you get through this, there are lots of places online and in bookstores to get more information. But this is a good place to start.
P.S. This is the second "Dummies" book I have recommended in a short space of time. What can I say? I find them well done introductions to any topic.
And if you are at all interested in DevOps, I recommend you go here and download it: here
DevOps for Dummies is a great introduction to the concepts of DevOps and covers alot of ground.
I highly recommend it.
For anyone looking to know more about private (IT) clouds, there's this: Private Cloud For Dummies, IBM Limited Edition - For Dummies .
IBM has teamed up with the Dummies publishers on a number of books. I
think this is a great idea. I am an employee of IBM and a fan of the
Dummies books: I hope this partnerships grows.