G4 or G.IV may refer to:

Places

County Route G4 (California) There are 21 routes assigned to the "G" zone of the California Route Marker Program, which designates county routes in California. The "G" zone includes county highways in Monterey County, California, Monterey, San Benito County, California, Sa ...

, a county highway in Santa Clara County, California, USA * G4 Beijing–Hong Kong and Macau Expressway, an expressway in China * G4 (Taichung Metro), also known as Songzhu Station or Jiushe Station, a station under construction in the Taichung Metro

Arts, entertainment, games, media

G4 (American TV network) G4 (also known as G4TV) was an American pay television and digital network owned by NBCUniversal and later Comcast Spectacor that primarily focused on video games. The network was originally owned by G4 Media (TV company), G4 Media, a joint v ...

, an American television channel *

G4 (Canadian TV channel) G4 was a Canadian English-language specialty television channel owned by Rogers Media. The name was licensed from NBCUniversal, whose parent company Comcast formerly owned a minority stake in the channel. Based on the U.S subscription networks ...

, a former Canadian television channel * G4 (group), a British vocal troupe *

Grob's attack Grob's Attack, or the Grob Opening, is an unconventional chess opening in which White begins with the move: : 1. g4 It is widely considered to be one of the worst possible first moves for White. International Master (IM) John Watson writes, " ...

, an opening move in chess

Groups, organisations, companies

G4 nations The G4 nations, comprising Brazil, Germany, India, and Japan, are four countries which support each other's bids for permanent seats on the United Nations Security Council. Unlike the G7, where the common denominator is the economy and long- ...

, four nations that support each other's bids to become permanent members of the United Nations Security Council: Brazil, Germany, India, and Japan * Big Four (Western Europe), sometimes called 'G4', a group of powerful countries in Europe * VIP Protection Unit, a unit of the Hong Kong Police Force (originally Section G, Division 4) *

Allegiant Air Allegiant Air is an American ultra low-cost carrier, ultra-low cost airline headquartered in Las Vegas, Nevada. The airline focuses on serving leisure traffic from small and medium-sized cities which it considers to be underserved, using an ult ...

, by IATA airline designator

Electrics, electronics, and computing

* G4, a type of

bi-pin lamp base A bipin or bi-pin (sometimes referred to as two-pin, bipin cap or bipin socket) is a type of light socket, lamp fitting. They are included in the International Electrotechnical Commission, IEC standard "IEC 60061 Lamp caps and holders together w ...

(socket), a lamp fitting where the pin spacing is 4mm * LG G4 smartphone * Moto G4, a line of smartphones * Group 4 compression, a type of image compression used in fax machines and some image file formats

Apple Computer

PowerPC G4 PowerPC G4 is a designation formerly used by Apple Inc., Apple to describe a ''fourth generation'' of 32-bit PowerPC microprocessors. Apple has applied this name to various (though closely related) processor models from Freescale Semiconductor, Fr ...

, a type of microprocessor by Freescale used by Apple **

Power Mac G4 The Power Mac G4 is a series of personal computers designed, manufactured, and sold by Apple Computer from 1999 to 2004 as part of the Power Macintosh line. Built around the PowerPC G4 series of microprocessors, the Power Mac G4 was marketed by ...

, a series of personal computers made by Apple Inc in July 1999 **

PowerBook G4 The PowerBook G4 is a series of notebook computers manufactured, marketed, and sold by Apple Computer between 2001 and 2006 as part of its PowerBook line of notebooks. The PowerBook G4 runs on the RISC-based PowerPC G4 processor, designed by t ...

, a series of Professional notebooks made by Apple Inc in 2001 **

iMac G4 The iMac G4 is an all-in-one personal computer designed, manufactured, and sold by Apple Computer from January 2002 to August 2004. The computer is comprised of a hemispheric base that holds the components, including a PowerPC G4 processor, ...

, a series of personal computer made by Apple Inc in January 2002 ** Xserve G4, an

Xserve The Xserve is a discontinued series of rack-mounted servers that was manufactured by Apple Inc. between 2002 and 2011. It was Apple's first rack-mounted server, and could function as a file server, web server or run high-performance computing ...

server made by Apple Inc in May 2002 ** iBook G4, an

iBook iBook is a line of laptop computers designed, manufactured, and sold by Apple Computer from 1999 to 2006. The line targeted entry-level, consumer and education markets, with lower specifications and prices than the PowerBook, Apple's higher- ...

series of consumer notebooks in October 2003 ** Mac Mini G4, a

Mac Mini Mac Mini (stylized as Mac mini) is a small form factor (desktop and motherboard), small form factor desktop computer developed and marketed by Apple Inc. It is one of the company's four current Mac (computer), Mac desktop computers, positioned ...

series of ultracompact computer in January 2005

Science and medicine

* G-4 (Ganesha-4), an amphetamine psychoactive drug and derivative of the psychedelic

Ganesha Ganesha or Ganesh (, , ), also known as Ganapati, Vinayaka and Pillaiyar, is one of the best-known and most worshipped Deva (Hinduism), deities in the Hindu deities, Hindu pantheon and is the Supreme God in the Ganapatya sect. His depictions ...

Vehicles

* AEG G.IV, a German World War I heavy bomber * Caudron G.4, a 1915 French biplane * Friedrichshafen G.IV, a 1918 German medium bomber * Gotha G.IV, a 1916 German heavy bomber *

Gulfstream IV The Gulfstream IV (or G-IV or GIV) and derivatives are a family of twinjet aircraft, mainly for private or Business jet, business use. They were designed and built by Gulfstream Aerospace, a General Dynamics company based in Savannah, Georgia, ...

, a family of private jet aircraft *

Mitsubishi G4M The Mitsubishi G4M is a twin-engine, land-based medium bomber formerly manufactured by the Mitsubishi Aircraft Company, a part of Mitsubishi Heavy Industries, and operated by the Air Service (IJNAS) of the Imperial Japanese Navy from 1940 to ...

"Betty", a World War II Japanese fast bomber *

Soko G-4 Super Galeb The Soko G-4 Super Galeb (from ), also referred to as N-62, is a Yugoslav single-engine, advanced jet trainer and light ground-attack aircraft designed by the Aeronautical Technical Institute at Žarkovo and manufactured by the SOKO aircraft f ...

, a jet trainer/light attack jet of Yugoslav origin * USS ''G4'' (SS-26), a 1914 G-class submarine of the United States Navy * G4-class freighter, a cargo ship design * LNER Class G4, a class of British steam locomotives * Pontiac G4, a compact car sold in Mexico

Other uses

* G4 EA H1N1, a strain of influenza *

G-quadruplex In molecular biology, G-quadruplex secondary structures (G4) are formed in nucleic acids by sequences that are rich in guanine. They are helical in shape and contain guanine tetrads that can form from one, two or four strands. The unimolecular ...

, a

DNA Deoxyribonucleic acid (; DNA) is a polymer composed of two polynucleotide chains that coil around each other to form a double helix. The polymer carries genetic instructions for the development, functioning, growth and reproduction of al ...

secondary structure *

Group 4 element Group 4 is the second group of transition metals in the periodic table. It contains only the four elements titanium (Ti), zirconium (Zr), hafnium (Hf), and rutherfordium (Rf). The group is also called the titanium group or titanium family after ...

, a class of elements on the Periodic Table * ATC code G04 ''Urologicals'', a subgroup of the Anatomical Therapeutic Chemical Classification System * Galactic 04 (G04), a Virgin Galactic suborbital tourist spaceflight in October 2023, the first spaceflight of a Pakistani