Graphane, the fully hydrogenated analogue of graphene, and its partially hydrogenated counterparts are attracting increasing attention. We review here its structure and predicted material properties, as well as the current methods of preparation. Graphane and hydrogenated graphenes are far more complex materials than graphene, expected to have a tuneable band gap via the extent of hydrogenation, as well as exhibit ferromagnetism. The methods for hydrogenated graphene characterization are discussed. We show that hydrogenation methods based on low or high pressure gas hydrogenation lead to less hydrogen saturation than wet chemistry methods based on variations of Birch reduction. The special cases of patterning of hydrogenated graphene strips in a graphene lattice are discussed.