Concat joins two or more arrays.
The method does not change the existing arrays and returns a copy of the joined array.
function Start () {
    var arr = new Array ("Hello", "World");
    var arr2 = new Array ("!");
    // joined now contains all 3 strings
    var joined = arr.Concat(arr2);
    // prints "Hello","World","!"
    print(joined);
}
Note: This is javascript only. C# does not use this feature.