> Thanks to everyone who replied. Particularly Matt, that is a fantastic
> analogy and exactly what I needed to present to the conference.

I hate to be too politically correct about this but I would be a little
cautious about presenting the analogy 'as is', as some people might find it
sexist and/or offensive.

I have found some confusion with users between Multi-processing,
multi-tasking and mult-threading & async operations.

To my mind:
1) Multi-processing : using more than one 'computer/processor' to perform
one or more tasks at once.  An example would be using a Linux Beowulf
cluster or a SGI 16 way CPU supercomputer to render pretty graphics.

2) Multi-tasking : Running more than one application/program at once
_independantly_ on a single machine.  For instance you can have POVRay
grinding running away rendering a picture then attempt to format a floppy.
Good test if your OS can really multi-task <g>. The OS should be handling
resource conflicts, critical sections (avoiding dead-locking) and giving
each task a slice at the processor without thrashing or getting too jumpy. 

3) Multi-threading : Dividing a single program up into multiple sub-tasks
that are seen by the user to run at the same time.  The programmer writing
the program controls creation & destruction of the threads, synchronisation
etc.  See the Delphi sort example...

4) Async operations.  I am on the ICS mail list and all the newbies see to
get confused by this.  For instance to get 10 simultanous downloads on a FTP
client they try writing 10 threads or using 10 copies of the FTP Client
component.  Basically with Async operations you send off a request like
'give me this web page' and then go on to do other things 'give me this
other web page' in the mean time.  Multi-things are occuring at the same
time (2 web pages are being sent down the line to you) but the programmer is
not concerned about threads...

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