Data storage medium

Data storage is the recording (storing) of information (data) in a storage medium. Recording is accomplished by virtually any form of energy. DNA and RNA, handwriting, phonographic recording, magnetic tape, and optical discs are all examples of storage media. Electronic data storage requires electrical power to store and retrieve data. Data storage in a digital, machine-readable medium is sometimes called digital data. Computer data storage is one of the core functions of a general purpose computer. Electronic documents can be stored in a much less space than paper documents.Barcodes and magnetic ink character recognition (MICR) are two ways of recording machine-readable data on paper.

In a 2007 study in Science it was estimated that the world's technological capacity to store information in analog and digital devices grew from less than 3 (optimally compressed) exabytes in 1986, to 295 (optimally compressed) exabytes in 2007, doubling roughly every 3 years.

In a less comprehensive study, the International Data Corporation estimated that the total amount of digital data was 281 exabytes in 2007, and had for the first time exceeded the amount of storage.

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