question about a term in Sparkfun hookup guide

Hello,

I’m not sure if this is the best forum to post in, but I think it’s relevant since I’m ultimately trying to use an Arduino to control a stepper motor. I’ve run across a term in the Sparkfun hookup guide for a stepper motor driver that I’ve never seen before: clock-in stepping. Can anyone please tell me what this means? Thank you!

Hello, could you please post the link of the material you’re studying? Thank you.