Hadoop streaming is a utility which allows you to create and run map/reduce job. It is a generic API that allows programs written in any languages to be used as Hadoop mapper.

Hadoop Streaming is a utility that comes with Apache Hadoop, a distributed storage and processing framework. It is a tool that allows users to create and run MapReduce jobs with any executable or script as the mapper and/or reducer.

In Hadoop Streaming, data is passed between the map and reduce tasks as text streams using standard input and output. This means that you can use any programming language or script that can read from standard input and write to standard output as long as it adheres to the Hadoop Streaming protocol.

This flexibility in language choice enables users to leverage existing code written in languages such as Python, Ruby, Perl, and others, within the Hadoop framework. It allows developers to harness the power of Hadoop for distributed data processing without having to write their code in Java, the native language for Hadoop MapReduce programs.