Back in the day, I used to care for a couple of labs full of Macs. Invariably, I’d find myself in the lab at the end of the day, shutting them all down for the night. I’d run up and down the rows of eMacs or whatever they were at the time, and hit the power button, then click on the Shut Down button. Or, if I was feeling frisky, I’d just hold down the power button until they shut off.
This took some time, needless to say. I wish I’d known of these useful keyboard commands to shut down or sleep the Macs, saving myself several minutes each day.