Learn in the textbookThe Five Basic Functions of a Computer
DefinitionStorage (記憶) is the function that holds programs and data so they can be read or written when needed.
ExplanationA computer places the program it will run in storage beforehand and then fetches its instructions one after another (the stored-program concept). The units that provide storage are main memory, which the CPU reads and writes directly, and auxiliary storage, which keeps programs and data for the long term, while the CPU itself also contains tiny storage locations called registers.
AnalogyIt resembles the difference between a note in your hand, papers spread on your desk, and files stored away in an archive. The closer something is, the faster you can use it, but the less of it fits.