echo

Just to muddy the water even further…

A web server frequently runs on a server, but could also run on a workstation, a phone, and many other devices. Said devices could be either physical or virtual.

All cars are automobiles, but not all automobiles are cars.

Another analog to the original is to say “a bank account and a checking account are different things”. While a checking account is a kind of bank account, not all bank accounts are checking accounts.

In some ways it’s like saying that an automobile and a car are different things.