Roos - Hadoop for dummies: [Understand the value of big data and how Hadoop can help manage it ; navigate the Hadoop 2 ecosystem and create clusters ; use applications for data mining, problem-solving,

Hadoop For Dummies

Published by: John Wiley & Sons, Inc., 111 River Street, Hoboken, NJ 07030-5774, www.wiley.com

Copyright 2014 by John Wiley & Sons, Inc., Hoboken, New Jersey

Published simultaneously in Canada

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Library of Congress Control Number: 2013954209

ISBN: 978-1-118-60755-8 (pbk); ISBN 978-1-118-65220-6 (ebk); ISBN 978-1-118-70503-2 (ebk)

Manufactured in the United States of America

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Chapter 1

In This Chapter

Seeing how Hadoop fills a need

Digging (a bit) into Hadoops history

Getting Hadoop for yourself

Looking at Hadoop application offerings

Organizations are flooded with data. Not only that, but in an era of incredibly cheap storage where everyone and everything are interconnected, the nature of the data were collecting is also changing. For many businesses, their critical data used to be limited to their transactional databases and data warehouses. In these kinds of systems, data was organized into orderly rows and columns, where every byte of information was well understood in terms of its nature and its business value. These databases and warehouses are still extremely important, but businesses are now differentiating themselves by how theyre finding value in the large volumes of data that are not stored in a tidy database.

The variety of data thats available now to organizations is incredible: Internally, you have website clickstream data, typed notes from call center operators, e-mail and instant messaging repositories; externally, open data initiatives from public and private entities have made massive troves of raw data available for analysis. The challenge here is that traditional tools are poorly equipped to deal with the scale and complexity of much of this data. Thats where Hadoop comes in. Its tailor-made to deal with all sorts of messiness. CIOs everywhere have taken notice, and Hadoop is rapidly becoming an established platform in any serious IT department.

This chapter is a newcomers welcome to the wonderful world of Hadoop its design, capabilities, and uses. If youre new to big data, youll also find important background information that applies to Hadoop and other solutions.

Like many buzzwords, what people mean when they say big data is not always clear. This lack of clarity is made worse by IT people trying to attract attention to their own projects by labeling them as big data, even though theres nothing big about them.