Animate an Image Based on the User's Input From the Keyboard

$(document).ready(function()
{
    $(document).keydown(function(key)
    {
        switch (parseInt(key.which, 10))
        {
            // Left arrow key pressed
            case 37:
                $('img').animate(
                {
                    left: "-=10px"
                }, 'fast');
                break;
                // Up Arrow Pressed
            case 38:
                $('img').animate(
                {
                    top: "-=10px"
                }, 'fast');
                break;
                // Right Arrow Pressed
            case 39:
                $('img').animate(
                {
                    left: "+=10px"
                }, 'fast');
                break;
                // Down Arrow Pressed
            case 40:
                $('img').animate(
                {
                    top: "+=10px"
                }, 'fast');
                break;
        }
    });
});