javascript append array to array

var colors=["red","white"];
colors.push("blue");//append 'blue' to colorsconst array1 = ['a', 'b', 'c'];
const array2 = ['d', 'e', 'f'];
const array3 = array1.concat(array2);const new_array = old_array.concat([value1[, value2[, ...[, valueN]]]])