how do libraries iterate through arrays code example

Example 1: loop array javascript

var colors = ['red', 'green', 'blue'];
	
	colors.forEach((color, colorIndex) => {
     console.log(colorIndex + ". " + color); 
    });

Example 2: what is the modern syntax for iterating through array using for loop in javascript

let friends=["jony","tom","Tejas"];
       friends.forEach(
           function f(i){
               console.log(i);
           }
       )