What is the difference between TEMP and DUMMY file?

[TempDummy]

What is the difference between TEMP and DUMMY file? Are not they just and serves the same purpose?

[William Collins]

If you mean a temporary dataset, starting with one or two ampersands, then No.

So what do you mean by "TEMP"?

DD DSN=NULLFILE is the equivalent of DD DUMMY.

[Robert Sample]

A DUMMY file provides an immediate end-of-file for input, and all data written for output is discarded immediately. A temporary file can have data for input or be used for output (or both in different steps of a job) -- consider it the same as any disk data set (it just goes away at the end of the job rather than staying around like disk data sets).