Are "jets" really jets?

From: (Daniel P. B. Smith)
Organization: The World Public Access UNIX, Brookline, MA
Date:         06 Sep 95 01:04:10 
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Do present-day commercial airliners really use "jet propulsion" to any
significant degree?  As I remember the way they explained it to us
in junior high school general science in the fifties, in a propellor plane
an engine turns a propeller which moves air and produces thrust.  In a
jet, the purpose of the turbines was not supposed to be to move air
directly, but to compress air (and to generate power to run the compressor).
The actual propulsion was supposed to come directly from reaction by the
expansion of hot gasses as a result of combustion, i.e. basically the
same as a rocket.

Is a modern-day "jet" really a jet at all, or is it just a kind of turboprop
where the propellor has lots of little blades and is concealed within
a cowling?
Daniel P. B. Smith