A gigabyte (derived from the SI prefix giga-) is a unit of information or computer storage meaning either exactly 1 billion bytes (1000³, or 10⁹) or approximately 1.07 billion bytes (1024³, or 2³⁰).^[1] Gigabyte (or Giga-byte) Technology is a Taiwan-based manufacturer of computer hardware products best known for its motherboards. ... This article is about the television program ReBoot. ... This article is about the unit of information. ... For the computer industry magazine, see Byte (magazine). ... An SI prefix (also known as a metric prefix) is a name or associated symbol that precedes a unit of measure (or its symbol) to form a decimal multiple or submultiple. ... It has been suggested that this article or section be merged with JEDEC. (Discuss) The JEDEC Solid State Technology Association is the semiconductor engineering standardization body of the Electronic Industries Alliance (EIA). ... In information technology there is sometimes confusion about measurement of bits and bytes. ... An SI prefix (also known as a metric prefix) is a name or associated symbol that precedes a unit of measure (or its symbol) to form a decimal multiple or submultiple. ... Look up giga- in Wiktionary, the free dictionary. ... The ASCII codes for the word Wikipedia represented in binary, the numeral system most commonly used for encoding computer information. ... This article does not cite any references or sources. ... For the computer industry magazine, see Byte (magazine). ...

The usage of the word "gigabyte" is ambiguous, depending on the context. When referring to RAM sizes and file sizes, it traditionally has a binary definition, of 1024³ bytes. For other uses, it means exactly 1000³ bytes. In order to address this confusion, currently the International Electrotechnical Commission (IEC) promotes the use of the term "gibibyte" for the binary definition. This position is endorsed by other standards organizations including the Institute of Electrical and Electronics Engineers (IEEE), the International Committee for Weights and Measures (CPIM) and the National Institute of Standards and Technology (NIST). Look up RAM, Ram, ram in Wiktionary, the free dictionary. ... // In computing, binary prefixes can be used to quantify large numbers where powers of two are more useful than powers of ten (such as computer memory sizes). ... The International Electrotechnical Commission (IEC) is an international standards organization dealing with electrical, electronic and related technologies. ... A gibibyte is a unit of information or computer storage. ... Not to be confused with the Institution of Electrical Engineers (IEE). ... The International Committee for Weights and Measures is the English name of the Comité international des poids et mesures (CIPM, sometimes written in English Comité International des Poids et Mesures). ... NIST logo The National Institute of Standards and Technology (NIST, formerly known as The National Bureau of Standards) is a non-regulatory agency of the United States Department of Commerce’s Technology Administration. ...

It is commonly abbreviated GB or Gbyte (not to be confused with Gb, which is used for a gigabit). A gigabit is a unit of information or computer storage, abbreviated Gbit or sometimes Gb. ...

Definition

There are two different definitions of gigabyte in general use:

• 1,000,000,000 bytes or 10⁹ bytes is the decimal definition, used in telecommunications (such as network speeds) and most computer storage manufacturers (such as hard disks and flash drives). This usage is compatible with SI. Quote from Seagate: "For drive storage capacity, 1 gigabyte = 1,000,000,000 bytes (or one billion bytes).",^[2] Similar quotes are found on the websites of other storage manufacturers.
• 1,073,741,824 bytes, equal to 1024³, or 2³⁰ bytes. This is the definition commonly used for computer memory and file sizes. Microsoft uses this definition to display hard drive sizes,^[3] as do most other operating systems and programs by default. By this definition, there are 1,024 times 1,024 times 1,024 bytes (or 1,024 megabytes where one megabyte is considered as 1048576 bytes) in a gigabyte. Since 1999, the IEC recommends that this unit should instead be called a gibibyte (abbreviated GiB). Although there is little other usage of the term "gigabyte" apart from referring to memory, file sizes, or storage capacity, the IEC's recommendations are frequently ignored amongst computer professionals, and "gigabyte" is used colloquially to mean 1024³ bytes. The standard body JEDEC Solid State Technology Association acknowledges the conflict and the existence of the IEC recommendations but, in recognition of the widespread colloquial usage, continues to recognize the definition of 1024³ bytes.^[4]

Copy of the original phone of Alexander Graham Bell at the Musée des Arts et Métiers in Paris Telecommunication is the assisted transmission of signals over a distance for the purpose of communication. ... This article does not cite any references or sources. ... Typical hard drives of the mid-1990s. ... A USB drive, shown with a 24 mm US quarter coin for scale. ... Look up si, Si, SI in Wiktionary, the free dictionary. ... The terms storage (U.K.) or memory (U.S.) refer to the parts of a digital computer that retain physical state (data) for some interval of time, possibly even after electrical power to the computer is turned off. ... Microsoft Corporation, (NASDAQ: MSFT, HKSE: 4338) is a multinational computer technology corporation with global annual revenue of US$44. ... An operating system (OS) is the software that manages the sharing of the resources of a computer and provides programmers with an interface used to access those resources. ... This article is about the year. ... The International Electrotechnical Commission (IEC) is an international standards organization dealing with electrical, electronic and related technologies. ... A gibibyte is a unit of information or computer storage. ... A colloquialism is an informal expression, that is, an expression not used in formal speech or writing. ... JEDEC Solid State Technology Association, formerly known as Joint Electron Device Engineering Council (JEDEC) or Joint Electron Device Engineering Councils, is the semiconductor engineering standardization body of the Electronic Industries Alliance (EIA), a trade association that represents all areas of the electronics industry. ...

Gigabytes vs. gigabits

In conventional modern usage, a byte is 8 bits. One gigabyte is equivalent to eight gigabits.

In computer networking, however, the conventional SI units are followed. Manufacturers of networking equipment always use 1000-bit kilobits as their basic unit of measurement.

Look up RAM, Ram, ram in Wiktionary, the free dictionary. ... A gigabit per second (Gbps or Gbit/s) is a unit of data transmission equal to 1,000 megabits per second or 1,000,000 kilobits per second or 1,000,000,000 bits per second. ...

Consumer confusion

As of 2007, most consumer hard drives are defined by their gigabyte-range capacities. The true capacity is usually some number above or below the class designation. Although most manufacturers of hard disks and Flash disks define 1 gigabyte as 1,000,000,000 bytes, the computer operating systems used by most users usually calculate a gigabyte by dividing the bytes (whether it is disk capacity, file size, or system RAM) by 1,073,741,824. This distinction is a cause of confusion, as a hard disk with a manufacturer rated capacity of 400 gigabytes may have its capacity reported by the operating system as only 372 GB, depending on the type of report. Year 2007 (MMVII) is the current year, a common year starting on Monday of the Gregorian calendar and the AD/CE era in the 21st century. ... Typical hard drives of the mid-1990s. ...

The difference between units based on SI and binary prefixes increases exponentially — in other words, an SI kilobyte is nearly 98% as much as a kibibyte, but a megabyte is under 96% as much as a mebibyte, and a gigabyte is just over 93% as much as a gibibyte. This means that a 500 GB hard disk drive would appear as "465 GB". As storage sizes get larger and higher units are used, this difference will become more pronounced.

Note that computer memory is addressed in base 2, due to its design, so memory size is always a power of two (or some closely related quantity, for instance 384 MiB = 3×2²⁷ bytes). It is thus convenient to work in binary units for RAM at the hardware level (for example, in using DIMM memory units). RAM memory size as seen by application software has no consistent bias towards power of two units, as the operating system will allocate memory in other granularities. Other computer measurements, like storage hardware size, data transfer rates, clock speeds, operations per second, etc., do not have an inherent base, and are usually presented in decimal units. The binary or base-two numeral system is a system for representing numbers in which a radix of two is used; that is, each digit in a binary numeral may have either of two different values. ... In mathematics, a power of two is any of the nonnegative integer powers of the number two; in other words, two times itself a certain number of times. ... RAM redirects here. ... Two types of DIMMs: a 168-pin SDRAM module (top) and a 184-pin DDR SDRAM module (bottom). ... This article does not cite any references or sources. ... The movement of data from one location to another is called data transfer. ... In synchronous digital electronics, such as most computers, a clock signal is a signal used to coordinate the actions of two or more circuits. ... For other uses, see Flop. ... In mathematics, the base or radix is the number of various unique symbols (digits), including zero, that a positional numeral system uses to represent numbers in a given counting system. ...

An example, take a hard drive that can store exactly 250×10⁹ or 250 billion bytes after formatting. Generally, operating systems calculate disk and file sizes using binary numbers, so this 250 GB drive would be reported as "232.83 GB". The result is that there is a significant discrepancy between what the consumer believes they have purchased and what their operating system says they have. An operating system (OS) is the software that manages the sharing of the resources of a computer and provides programmers with an interface used to access those resources. ...

Some consumers feel short-changed when they discover the difference, and claim that manufacturers of drives and data transfer devices are using the decimal measurements in an intentionally misleading way to inflate their numbers. Several legal disputes have been waged over the confusion. See Binary prefix — Legal disputes. // In computing, binary prefixes can be used to quantify large numbers where powers of two are more useful than powers of ten (such as computer memory sizes). ...

To further complicate matters, flash memory chips are organized in multiples of 2, but retail flash memory products have available capacities specified by multiples of 10. Removable flash storage products contain file systems that make the devices behave like hard disks instead of RAM, yet it is called 'memory'. In operating systems like Windows Vista, flash memory can indeed be treated like RAM. A USB flash drive. ... RAM redirects here. ... Windows Vista is a line of graphical operating systems used on personal computers, including home and business desktops, notebook computers, Tablet PCs, and media centers. ...

The basis of the problem is that the official definition of the SI units is not well known,^{[citation needed]} and some legal settlements include directions for manufacturers to use clearer info, e.g. by stating a hard disk's size in both GB and GiB. However, JEDEC memory standards still uses the IEEE 100 nomenclatures. It has been suggested that this article or section be merged with JEDEC. (Discuss) The JEDEC Solid State Technology Association is the semiconductor engineering standardization body of the Electronic Industries Alliance (EIA). ...

Gigabytes in use

Trivia sections are discouraged under Wikipedia guidelines. The article could be improved by integrating relevant items and removing inappropriate ones.

• The human genome contains 0.791175 GB of data (the 3.1647×10⁹ base pairs[1] represented as 2-bits).
• A DVD-5 format disc is specified as capable of storing 4.7 gigabytes (4,700,000,000 bytes), or roughly 4.38 gibibytes. A DVD-9 is capable of storing 8.5 gigabytes, or roughly 7.91 gibibytes.
• One gigabyte can hold over 1000 novels (uncompressed at 100,000 words per novel).
• One gigabyte is roughly equal to 18 hours of MP3 music at 128 kbit/s (1,024³ / 128 / 1000 * 8 / 3600 = 18.64).
• One gigabyte is roughly equivalent to 12 hours of Flash Video (at 450x370).
• All 6th generation and 7th generation game consoles have game discs that are around 1 GB or more:Dreamcast (GD-ROM - 1.2 GB), Nintendo GameCube (MiniDVD - 1.5 GB), PlayStation 2, Xbox, Xbox 360, and Wii (DVD - 8.5 GB), and PlayStation 3 (Blu-ray Disc - 50 GB).
• Dual-layer Blu-ray Discs and dual-layer HD DVD discs can hold about 50 gigabytes (50,000,000,000 bytes) and 30 gigabytes (30,000,000,000 bytes) of data, respectively.

Image File history File links Broom_icon. ... A graphical representation of the normal human karyotype. ... In genetics, two nucleotides on opposite complementary DNA or RNA strands that are connected via hydrogen bonds are called a base pair (often abbreviated bp). ... This article is about the unit of information. ... DVD (also known as Digital Versatile Disc or Digital Video Disc) is a popular optical disc storage media format. ... A gibibyte is a unit of information or computer storage. ... For other uses, see MP3 (disambiguation). ... Flash Video is the name of a file format used to deliver video over the Internet using Adobe Flash Player (formerly known as Macromedia Flash Player) version 6, 7, 8, or 9. ... The sixth-generation era (sometimes inaccurately referred to as the 128-bit era; see section below) refers to the computer and video games, video game consoles, and video game handhelds available at the turn of the 21st century. ... The seventh generation era (sometimes referred to as the HD era or the Touch! Generation) is a video game era in the history of computer and video games that began towards the end of 2004, but is not set to really take off until late 2005/early 2006 with the... The Dreamcast , code-named White Belt, Black Belt, Dural, Dricas, Vortex, Katana, Shark, and Guppy during development) is Segas last video game console and the successor to the Sega Saturn. ... GD-ROM is the proprietary optical disc format used by the Sega Dreamcast. ... The Nintendo GameCube (GCN) is Nintendos fourth home video game console, belonging to the sixth generation era. ... There are two types of MiniDVD cDVD, which are 80-mm versions of the 120-mm DVD mini-DVD, which are standard CDs filled with the DVD-video format // cDVD A Mini-DVD-RAM with DVD Round Holder. ... PS2 redirects here. ... The Xbox is a sixth generation era video game console produced by Microsoft Corporation. ... It has been suggested that Xbox 360 Elite be merged into this article or section. ... The Wii (pronounced as the pronoun we, IPA: ) is the fifth home video game console released by Nintendo. ... DVD (also known as Digital Versatile Disc or Digital Video Disc) is a popular optical disc storage media format. ... The PlayStation 3 , trademarked PLAYSTATION®3,[3] commonly abbreviated PS3) is the third home video game console produced by Sony Computer Entertainment; successor to the PlayStation 2. ... Blu-ray Disc (also known as Blu-ray or BD) is an optical disc storage media format. ... Blu-ray Disc (also known as Blu-ray or BD) is an optical disc storage media format. ... HD-DVD disc HD DVD (for High Density Digital Versatile Disc) is a digital optical media format which is being developed as one standard for high-definition DVD. HD DVD is similar to the competing Blu-ray Disc, which also uses the same CD sized (120 mm diameter) optical data...

See also

• Binary prefix
• JEDEC memory standards
• Orders of magnitude (data)

// In computing, binary prefixes can be used to quantify large numbers where powers of two are more useful than powers of ten (such as computer memory sizes). ... It has been suggested that this article or section be merged with JEDEC. (Discuss) The JEDEC Solid State Technology Association is the semiconductor engineering standardization body of the Electronic Industries Alliance (EIA). ... This is a list of orders of magnitude for data (or information), measured in bits. ...

References

1. ^ 1000³ = one billion.
2. ^ Industry Terms Glossary: Gigabyte.
3. ^ HP Notebook PCs - Size of Disk Drive Does not Match Specifications (Windows XP).
4. ^ JEDEC Solid State Technology Association (December 2002), "Terms, Definitions, and Letter Symbols for Microcomputers, Microprocessors, and Memory Integrated Circuits", JESD 100B.01, <http://www.jedec.org/download/search/JESD100B01.pdf>

One thousand million (1,000,000,000) is the natural number following 999,999,999 and preceding 1,000,000,001. ...

External links

• http://physics.nist.gov/cuu/Units/binary.html
• http://www.iec.ch/zone/si/si_bytes.htm
• http://www.quinion.com/words/turnsofphrase/tp-kib1.htm
• http://www.nist.gov/public_affairs/techbeat/tb9903.htm