remove multiple elements from array in javascript code example

Example 1: javascript removing items looping through array

var colors=["red","green","blue","yellow"];
//loop back-words through array when removing items like so:
for (var i = colors.length - 1; i >= 0; i--) {
    if (colors[i] === "green" || colors[i] === "blue") { 
        colors.splice(i, 1);
    }
}
//colors is now  ["red", "yellow"]

Example 2: js remove several elements from array

var arr1 = [1, 2, 3, 4, 5, 6];var arr2 = arr1; // Reference arr1 by another variable arr1 = [];console.log(arr2); // Output [1, 2, 3, 4, 5, 6]