Most people have heard of hardware (the physical machine and its components) and software (the programs that run on the hardware). A few will have also heard of firmware (usually low-level software which makes hardware work).
On the other side of the keyboard, sits the wetware - the usually carbon-based 97%-H
2O life-form who instructs the computer... So, if you ever hear that the problem is with the wetware, you'll know what the tech is talking about...

The user (also "luser" pronounced "loser" - from the bearded world of Unix) may also be referred to as the nut behind the keyboard.