Systemload output from "w": what does it mean?

[Bill Irwin]

I like the output from the "w" command and use it instead of "finger".  I
like  seeing the current process running for each user.  It also gives me
some info that I am curious about.

It  reports  "load  average" followed by three sets  of  numbers.   These
numbers  get  higher as more users come on the system, as  they  probably
should,  but why three of them?  What is considered medium or heavy  load
conditions?  Is it measuring cpu usage and/or swapping and/or disk i/o?

I  am running SCO XENIX 2.3.2.  The help command doesn't know about  "w".
Anyone familiar with this?
-- 
Bill Irwin    -   TWG The Westrheim Group     -    Vancouver, BC, Canada
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