What is a vector and how does it point and push?
Arrow's Secret Job
What is a vector and how does it point and push?
Some things in life just need a number. Three apples. Five o'clock. Ninety degrees of summer. But other things need a number AND a direction, or they make no sense at all. "Walk five steps," I say — but five steps WHICH WAY? That little gap, that "which way," is where a vector lives.
So here is the whole idea in one breath: a vector is an arrow. That's it. An arrow has two jobs, and it never does just one. It points somewhere (that's its direction), and it has a length (that's its size, which we call magnitude). Long arrow, big push. Short arrow, gentle nudge.
