If you can pick it up, it’s a PC.
If you can’t pick it up but you can push it over, it’s a minicomputer.
But when you can’t pick it up or knock it over, it’s a mainframe.
Once a programmer drowned in the sea. Many Marines where at that time on the beach, but the programmer was shouting “F1 F1” and nobody understood it.
The boy is smoking and leaving smoke rings into the air.
The girl gets irritated with the smoke and says to her lover: “Can’t you see the warning written on the cigarettes packet, smoking is injurious to health!”
The boy replies back: “Darling, I am a programmer. We don’t worry about warnings, we only worry about errors.”