Data storage refers to the technology and physical principles used to retain digital information for later retrieval. These methods utilize various physical media, ranging from magnetic materials that store data through polarization to optical discs that employ laser reflectivity, and advanced semiconductor devices that trap electrical charge. Information is fundamentally represented in binary digits (bits), which can be stored by changing the state of a physical property, such as magnetic orientation or electrical charge level. The evolution of data storage capacity and density has been driven by advances in material science and miniaturization, leading to increasingly high-volume, non-volatile, and efficient systems capable of managing the rapidly growing amount of digital data.