<script src="../OpenLayers.js"></script>
<script type="text/javascript">
    var map, layer;

    function init(){
        map = new OpenLayers.Map( 'map' );
        layer = new OpenLayers.Layer.WMS( "OpenLayers WMS",
                "http://localhost:8090/geoserver/worksapce/wms", {layers: 'basic'} );
        var layer_1=new OpenLayers.Layer.WMS( "OpenLayers WMS",
                "http://localhost:8090/geoserver/worksapce/wms",
                 {
                 layers:"states",
                 format:'image/png'
                 },
                 {isBaseLayer:false}

                 );

        map.addLayer([layer,layer_1);


        map.addControl( new OpenLayers.Control.LayerSwitcher() );
    }
</script>