var myArray = [ 'a', 'b', 'c' ];

var i;

var len = myArray.length;

​

// we'll use the variable i as our index; it starts at 0,

// and we increment it by 1 (using i++) until i is no longer

// less than the length of the array

for (i = 0; i < len; i = i + 1) {

  log( 'item at index ' + i + ' is ' + myArray[ i ] );

}