Geolocation

<p class="intro" id="demo">Click the button to see where you are!
 <button onclick="getLocation()">click me to see where you are!</button></p>

<div id="mapholder"></div>
<script src="http://maps.google.com/maps/api/js?sensor=false"></script>
<script>
   var x=document.getElementById("demo");
   function getLocation()
   {
   if (navigator.geolocation)
   {
   navigator.geolocation.getCurrentPosition(showPosition,showError);
   }
   else{x.innerHTML="Geolocation is not supported by this browser.";}
   }

function showPosition(position)
   {
   lat=position.coords.latitude;
   lon=position.coords.longitude;
   latlon=new google.maps.LatLng(lat, lon)
   mapholder=document.getElementById('mapholder')
   mapholder.style.height='250px';
   mapholder.style.width='623px';

 var myOptions={
   center:latlon,zoom:14,
   mapTypeId:google.maps.MapTypeId.ROADMAP,
   mapTypeControl:false,
   navigationControlOptions:{style:google.maps.NavigationControlStyle.SMALL}
   };
   var map=new google.maps.Map(document.getElementById("mapholder"),myOptions);
   var marker=new google.maps.Marker({position:latlon,map:map,title:"You are here!"});
   }

function showError(error)
   {
   switch(error.code) 
   {
   case error.PERMISSION_DENIED:
   x.innerHTML="User denied the request for Geolocation."
   break;
   case error.POSITION_UNAVAILABLE:
   x.innerHTML="Location information is unavailable."
   break;
   case error.TIMEOUT:
   x.innerHTML="The request to get user location timed out."
   break;
   case error.UNKNOWN_ERROR:
   x.innerHTML="An unknown error occurred."
   break;
   }
   }
   </script>

Click the button to see where you are! click me to see where you are!