The maps are taken from OpenStreetMap, a collaborative world map that was developed the same way as Wikipedia.
You can use Emerillon to explore maps visually, search map contents, and save locations to access later.
An interesting feature is the different kinds of views available besides the original one. You can view a bike routes map, a public transportation map, and a terrain map.
Emerillon can have even more features if you install plugins. In fact, many of its features are provided by plugins that you can configure from the add-ons panel.