The comparison operator that returns -1, 0, or 1 depending on how the operands compare is often represented as <=> and commonly referred to as the "spaceship operator" because it looks like a flying saucer viewed from the side.

http://en.wikipedia.org/wiki/Spaceship_operator

Huh. I never heard it called that before.

My background is in math so I always though of it in terms of the sign function: http://en.wikipedia.org/wiki/Sign_function

spaceship(x,y) = sign(x-y), for numbers, anyhow.

FWIW, Larry Wall calls it the Spaceship Operator in "Programming Perl".