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My free -m

free -m
              total        used        free      shared  buff/cache   available
Mem:           7971        1834        2878          79        3257        5713
Swap:          8179           0        8179

What is Mem and what is Swap?

marked as duplicate by GAD3R, techraf, Jakuje, steve, Community Dec 5 '16 at 20:25

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  • There's a very fine manual page for this command, worthy of a read - linux.die.net/man/1/free – steve Dec 5 '16 at 16:52
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    @steve and where in that fine manual page is the difference between swap and physical memory explained? Where is the meaning of "shared" or "buff/cache" explained? At best the man page has informative stubs that are clear to those of us who already know what shared memory is, it isn't very helpful to a new user. – terdon Dec 5 '16 at 17:18
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    To the question's credit, it is clearly written. It has a simple answer, so I submitted one. – SauceCode Dec 5 '16 at 19:01

Quoting from the man page:

free displays the total amount of free and used physical and swap memory in the system

And your -m flag displays those amounts in megabytes.

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