GameRegistry Line for all new Forge Items?

Hello Forge experts,

I'm trying to really understand the code and there's one line that Forge implements that I don't quite get.

It's the GameRegistry.registerItem line....

In the forge class, it says this:

    * Register an item with the item registry with a custom name : this allows for easier server-client resolution

    * @param item The item to register

    * @param name The mod-unique name of the item

    public static void registerItem(net.minecraft.item.Item item, String name)

    {

        registerItem(item, name, null);

    }

Does anyone know  what it's doing to allow for easier server; client resolution and what exactly a "mod-unique" name is?

If I have this code:

//  LOAD THE SWORD

    MySword_1 = new MySword(2234, ToolMaterial.IRON).setUnlocalizedName("MySword_1");

    GameRegistry.registerItem(MySword_1, "MySword_1");

    LanguageRegistry.addName(MySword_1, "My Awesome Sword");

If I remove the GameRegistry Line, nothing seems to happen...

Any ideas?