JavaScript: Openlayers Map Starting Template

gistfile1

function loadMap()
{
	//create map object
			map = new OpenLayers.Map({
				div: "map",
				projection: "EPSG:900913"
			});
			
			map.addLayer(
				new OpenLayers.Layer.XYZ("esri", 'http://server.arcgisonline.com/ArcGIS/rest/services/World_Street_Map/MapServer/tile/${z}/${y}/${x}', {
					transitionEffect: "resize",
					sphericalMercator: true,
					format: "image/jpg"
				}));
			map.addControl(new OpenLayers.Control.LayerSwitcher());	
			map.setCenter(new OpenLayers.LonLat(-2054627.3200196, 1291480.0297267), 3);
}