how does foreach work in js code example

Example 1: for each javascript

let numbers = ['one', 'two', 'three', 'four'];

numbers.forEach((num) => {
  console.log(num);
});  // one   //two //three // four

Example 2: javascript foreach syntax

const marks = [12, 17, 14];
let sum = 0;

marks.forEach(mark => {
  sum += mark;
});