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These steps ensure that Hadoop is installed and available from the command line. By setting the path and configuration variables, we can use the Hadoop command-line tool. The modification to the Hadoop configuration file is the only required change to the setup needed to integrate with your host settings.

As mentioned earlier, you should put the export commands in your shell startup file or a standalone-configuration script that you specify at the start of the session.

Don't worry about some of the details here; we'll cover Hadoop setup and use later.