[SunHELP] clarification - what does the 'f' option do in the tar and jar commands?

[Solaris Neophyte]

i'm confused as to what this option does exactly... I see it all the time in examples...in my solaris text is says the following which is entirely cryptic to me... tarf - Specifices the archivefile or tape device.  The default tape device is /dev/rmt/0.  If archivefile is "-", then the tar command reads from standard input or writes to standard output, whichever is appropriatejarf - Specifies the jar file or tape drive.  The jar command sends the data to the screen if the "f" option is not used.can someone explain this to me?  from what I gather you have to use the f option to tell it that the following filename or location is where you want to store (or is it copy) the archived file?  now what happens if you don't specify a location for either command?
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