Why are the first episodes of shows called Pilot?

Question

I've noticed that the name of the first episodes of some shows, for example, the office, or that 70's show, the title of episode 1 is Pilot.

Does anyone know the reason for this?

Answer 1

The pilot ep. is where they make an episode to deliver to the networks in the hope it will gain further funding for a series. Hundreds of pilots are made annually, but very few become a full series. Why it's called pilot? not 100% sure. It could be like a pilot light, or template for the rest, but pilot it is.  

Answer 2

In addition to what the above says, I always thought it was called Pilot, because it is the "liftoff" of a series.

or as google has as one of it's definition:

A television program produced as a prototype of a series being considered a network. The success or failure of the pilot usually determines if the network picks up the series.

and....

Another definition:

a sample of a proposed television series.

Answer 3

maybe because a pilot sorta starts a plane, and so the pilot of a tv starts a series. LOL i dunno actually, i just think that.