Random Integers and Floats

var a = Math.random();

Sample value of a: 0.21322848065742162

Math.random() returns a random number between 0 (inclusive) and 1 (exclusive)

function getRandom() {
    return Math.random();
}

To use Math.random() to get a number from an arbitrary range (not [0,1)) use this function to get a random number between min (inclusive) and max (exclusive): interval of [min, max)

function getRandomArbitrary(min, max) {
  return Math.random() * (max - min) + min;
}

To use Math.random() to get an integer from an arbitrary range (not [0,1)) use this function to get a random number between min (inclusive) and max (exclusive): interval of [min, max)

function getRandomInt(min, max) {
  return Math.floor(Math.random() * (max - min)) + min;
}

To use Math.random() to get an integer from an arbitrary range (not [0,1)) use this function to get a random number between min (inclusive) and max (inclusive): interval of [min, max]

function getRandomIntInclusive(min, max) {
  return Math.floor(Math.random() * (max - min + 1)) + min;
}

Functions taken from https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/Math/random