CODE EXAMPLE FOR JAVASCRIPT

array.map

let arr = [1,2,3]

/*
  map accepts a callback function, and each value of arr is passed to the 
  callback function. You define the callback function as you would a regular
  function, you're just doing it inside the map function
  
  map applies the code in the callback function to each value of arr, 
  and creates a new array based on your callback functions return values
*/
let mappedArr = arr.map(function(value){
	return value + 1
})

// mappedArr is:
> [2,3,4]