Three engineers are riding down the road.

One is a mechanical engineer, one is an electrical engineer, and one is a computer engineer.

The car breaks down and coasts to the side of the road.

"Hang on," says the mechanical engineer. "The problem is probably the engine, let me have a look at it and I'll have us on the road again in no time."

"Wait," says the electrical engineer. "The way it just stopped like that, I think it's the electrical system. Let me have a look and I'll get us going again in a minute or two."

"Hold on," says the computer engineer. "Why don't we all just get out of the car and get in again, and then see if it starts?"