Graphene, which is a variant of the element carbon, is found naturally in graphite. Graphene is only one molecular layer thick, and is therefore known as two dimensional, 2D. Only ten years ago, one succeeded for the first time to isolate graphene. Since then, strong research efforts have led to a broad knowledge of the subject. There are a large number of appication fields for graphene, electrically conductive inks and energy storage, are two good examples. Besides graphene, nature has provided us with a number of other 2D materials with similar material properties.