How do i see the actual memory usage?

[Søren Neigaard <s.neigaard@xxxxxxxxxxxxxx>]

if i do a "top" it always uses almost all memory, no matter if nothing 
is running on my system, so im guessing that "top" does not show me the 
actual memory usage, but rather the memory the system has "reserved" or 
something.

So is there a way to see the actual memory usage, so i can see how much 
memory is actuall available on the system?

--
Med venlig hilsen/Best regards
Søren Neigaard
System Architect
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Mobilethink A/S
Arosgaarden
Åboulevarden 23, 4.sal
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Telefon: +45 86207800
Direct: +45 86207810
Fax: +45 86207801
Email: s.neigaard@xxxxxxxxxxxxxx
Web: www.mobilethink.dk
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