Data storage is the recording (storing) of
Information is an abstract concept that refers to that which has the power to inform. At the most fundamental level information pertains to the interpretation of that which may be sensed. Any natural process that is not completely random, ...
) in a storage medium. Handwriting,
A phonograph, in its later forms also called a gramophone (as a trademark since 1887, as a generic name in the UK since 1910) or since the 1940s called a record player, or more recently a turntable, is a device for the mechanical and analogu ...
Magnetic tape is a medium for magnetic storage made of a thin, magnetizable coating on a long, narrow strip of plastic film. It was developed in Germany in 1928, based on the earlier magnetic wire recording from Denmark. Devices that use magne ...
In computing and optical disc recording technologies, an optical disc (OD) is a flat, usually circular disc that encodes binary data (bits) in the form of pits and lands on a special material, often aluminum, on one of its flat surfaces. ...
s are all examples of storage media. Biological molecules such as RNA
are considered by some as data storage.
Recording may be accomplished with virtually any form of
In physics, energy (from Ancient Greek: ἐνέργεια, ''enérgeia'', “activity”) is the quantitative property that is transferred to a body or to a physical system, recognizable in the performance of work and in the form of heat ...
. 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
A computer is a machine that can be programmed to carry out sequences of arithmetic or logical operations ( computation) automatically. Modern digital electronic computers can perform generic sets of operations known as programs. These p ...
. Electronic document
s can be stored in much less space than paper
A document is a written, drawn, presented, or memorialized representation of thought, often the manifestation of non-fictional, as well as fictional, content. The word originates from the Latin ''Documentum'', which denotes a "teaching" or ...
A barcode or bar code is a method of representing data in a visual, machine-readable form. Initially, barcodes represented data by varying the widths, spacings and sizes of parallel lines. These barcodes, now commonly referred to as linear or o ...
s and magnetic ink character recognition
(MICR) are two ways of recording machine-readable data on paper.
A recording medium is a physical material that holds information. Newly created information is distributed and can be stored in four storage media–print, film, magnetic, and optical–and seen or heard in four information flows–telephone, radio and TV, and the Internet
as well as being observed directly. Digital information is stored on electronic media
in many different
A recording format is a format for encoding data for storage on a storage medium. The format can be container information such as sectors on a disk, or user/audience information (content) such as analog stereo audio. Multiple levels of enc ...
With electronic media
, the data and the recording media are sometimes referred to as "software" despite the more common use of the word to describe
Software is a set of computer programs and associated documentation and data. This is in contrast to hardware, from which the system is built and which actually performs the work.
At the lowest programming level, executable code consists ...
. With ( traditional art
) static media, art materials
A crayon (or wax pastel) is a stick of pigmented wax used for writing or drawing. Wax crayons differ from pastels, in which the pigment is mixed with a dry binder such as gum arabic, and from oil pastels, where the binder is a mixture of wax an ...
s may be considered both equipment and medium as the wax, charcoal or chalk material from the equipment becomes part of the surface of the medium.
Some recording media may be temporary either by design or by nature. Volatile organic compound
s may be used to preserve the environment
or to purposely make data expire over time. Data such as
The smoke signal is one of the oldest forms of long-distance communication. It is a form of visual communication used over a long distance. In general smoke signals are used to transmit news, signal danger, or to gather people to a common area ...
Skywriting is the process of using one or more small aircraft, able to expel special smoke during flight, to fly in certain patterns that create writing readable from the ground. These messages can be advertisements, general messages of celebra ...
are temporary by nature. Depending on the volatility, a gas
An atmosphere () is a layer of gas or layers of gases that envelop a planet, and is held in place by the gravity of the planetary body. A planet retains an atmosphere when the gravity is great and the temperature of the atmosphere is low. A ...
Smoke is a suspension of airborne particulates and gases emitted when a material undergoes combustion or pyrolysis, together with the quantity of air that is entrained or otherwise mixed into the mass. It is commonly an unwanted by-produc ...
) or a liquid surface such as a
A lake is an area filled with water, localized in a basin, surrounded by land, and distinct from any river or other outlet that serves to feed or drain the lake. Lakes lie on land and are not part of the ocean, although, like the much large ...
would be considered a temporary recording medium if at all.
Global capacity, digitization, and trends
The University of California, Berkeley (UC Berkeley, Berkeley, Cal, or California) is a public land-grant research university in Berkeley, California. Established in 1868 as the University of California, it is the state's first land-grant univ ...
report estimated that about five
The byte is a unit of digital information that most commonly consists of eight bits. Historically, the byte was the number of bits used to encode a single character of text in a computer and for this reason it is the smallest addressable un ...
s of new information were produced in 2002 and that 92% of this data was stored on hard disk drives. This was about twice the data produced in 2000. The amount of data transmitted over telecommunication systems in 2002 was nearly 18 exabytes—three and a half times more than was recorded on non-volatile storage. Telephone calls constituted 98% of the telecommunicated information in 2002. The researchers' highest estimate for the growth rate of newly stored information (uncompressed) was more than 30% per year.
''Science'', also widely referred to as ''Science Magazine'', is the peer-reviewed academic journal of the American Association for the Advancement of Science (AAAS) and one of the world's top academic journals.
It was first published in 1880, ...
article estimated that the year 2002 was the beginning of the digital age for information storage: an age in which more information is stored on digital storage devices than on analog storage devices.
In 1986, approximately 1% of the world's capacity to store information was in digital format; this grew to 3% by 1993, to 25% by 2000, and to 97% by 2007. These figures correspond to less than three compressed exabytes
in 1986, and 295 compressed exabytes in 2007.
The quantity of digital storage doubled roughly every three years.
In a more limited study, the International Data Corporation
estimated that the total amount of digital data in 2007 was 281 exabytes, and that the total amount of digital data produced exceeded the global storage capacity for the first time.
History of Computer Data Storage
History of Storage from Cave Paintings to ElectronsThe Evolution of Data Storage
Film and video technology
Mass media technology
Sound production technology