Leaflet demo

For update marker position

HTML

<script src="http://cdn.leafletjs.com/leaflet-0.7.2/leaflet.js"></script>
<link rel="stylesheet" href="http://cdn.leafletjs.com/leaflet-0.7.2/leaflet.css">
<div id="map"></div>

CSS

#map {
  height: 600px;
  width: 100%;
}

JavaScript

var osmUrl = 'http://{s}.tile.osm.org/{z}/{x}/{y}.png',
    osm = L.tileLayer(osmUrl, {
                noWrap: true,
                attribution: "<a href='http://openstreetmap.org'>OpenStreetMap</a>"
            });

var map = L.map('map').setView([0, 0], 1).addLayer(osm);