$TemporaryDirectory

gives the main system directory for temporary files on your computer system.

Details

$TemporaryDirectory gives the directory where files are created when no explicit file is specified in OpenWrite, CreateDirectory and related functions.
On Unix-based systems, the default setting for $TemporaryDirectory is typically /tmp.
The Wolfram System does not automatically delete files it creates in the $TemporaryDirectory directory, although the operating system may do so.

Show the path for the temporary directory:

Open a stream for writing in the temporary directory:

Close the stream:

Print the resulting file:

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