Amazon Elastic MapReduce (Amazon EMR) is a web service that makes it easy to process large amounts of data efficiently. Amazon EMR uses Hadoop processing combined with several AWS products to do such tasks as web indexing, data mining, log file analysis, machine learning, scientific simulation, and data warehousing.

Developer Guide
Provides a conceptual overview of Amazon Elastic MapReduce and includes detailed development instructions for using the various features.
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  API Reference
Describes all the API operations for Amazon Elastic MapReduce in detail. Also provides sample requests, responses, and errors for the supported web services protocols.
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