OpenLayers
A high-performance, feature-packed library for all your mapping needs
...It can display map tiles, vector data and markers loaded from any source. OpenLayers has been developed to further the use of geographic information of all kinds. It is completely free, Open Source JavaScript, released under the 2-clause BSD License (also known as the FreeBSD). Pull tiles from OSM, Bing, MapBox, Stamen, and any other XYZ source you can find. OGC mapping services and untiled layers also supported. Render vector data from GeoJSON, TopoJSON, KML, GML, Mapbox vector tiles, and other formats. Leverages Canvas 2D, WebGL, and all the latest greatness from HTML5. ...