What is between?

[RazvanBugoi]

https://www.codewars.com/kata/55ecd718f46fba02e5000029/train/javascript

[RazvanBugoi]

function between(a, b) {
  let output = [];
  for (let i=a; i<=b; i++) {
  output.push(i);
  };
  return output;
}