Disclosed are medium and methods for storage and reading of stored information. The storage medium comprises an oxide layer having a plurality of pits and projections on the oxide layer surface. Information storage is achieved by applying voltage or light, in accordance to information signals, to the oxide layer, to differentially heat said oxide layer and create a plurality of portions which contain different quantities of oxygen. Stored information is read by the application of voltage or light to the oxide layer containing a plurality of portions containing different quantity of oxygen and detection of the electrical resistance or light reflectivity of each of said plurality of portions.