Google is always taking people by storm, and now they are taking people to Mars. Just like the normal Google Maps you can switch between different modes: Elevation, Visible, and Infrared. These are the differences between the different modes:
Elevation – A shaded relief map, generated with data from the Mars Orbiter Laser Altimeter (MOLA) on NASA’s Mars Global Surveyor spacecraft. This map is color-coded by altitude, so you can use the color key at the lower left to estimate elevations. Visible – A mosaic of images taken by the Mars Orbiter Camera (MOC) on NASA’s Mars Global Surveyor spacecraft. MOC is like the digital camera you have at home. Basically, this is what your eyes would see if you were in orbit around Mars. Infrared – A mosaic of infrared images taken by the Thermal Emission Imaging System (THEMIS) on NASA’s Mars Odyssey spacecraft. Warmer areas appear brighter, and colder areas are darker. Clouds and dust in the atmosphere are transparent in the infrared, making this the sharpest global map of Mars that’s ever been made.
It is fun to play with but is not really something that you would use on a daily basis. I think Google was just shooting for something really really unique from its competitors.