Mapstraction is a Javascript library. It provides developers with a single interface for a wide variety of Javascript map APIs including Leaflet, Google, Bing, OpenLayers and ESRI's ArcGIS.
A key benefit is that once a developer has loaded Mapstraction, s/he can to switch from one map API to another quickly and easily - often only needing to change a few lines of code.
Mapstraction displays points, lines, polygons and markers on the maps, and also allows developers to add base maps and overlays.