From Quiz Revision Notes


The Colossus machines were electronic computing devices used by British codebreakers to read encrypted German messages during World War II. These were the world's first programmable, digital, electronic, computing devices. They used vacuum tubes (thermionic valves) to perform the calculations. Colossus was designed by engineer Tommy Flowers

ENIAC (Electronic Numerical Integrator And Computer) was the first general-purpose electronic computer. Designed for the US Army in 1946

EDSAC (Electronic Delay Storage Automatic Calculator) was constructed by Maurice Wilkes and his team at the University of Cambridge Mathematical Laboratory. Later the project was supported by J. Lyons & Co. Ltd., who were rewarded with the first commercially applied computer, LEO I, based on the EDSAC design. EDSAC ran its first programs in1949

Ferranti Mark I was the world's first commercially available general- purpose electronic computer. The first machine was delivered to the University of Manchester in February 1951, just ahead of the UNIVAC which was delivered to the United States Census Bureau a month later

Altair 8800 – first PC, designed in 1975

Flash memory (both NOR and NAND types) was invented by Dr. Fujio Masuoka while working for Toshiba in 1984

Ray Tomlinson invented email and the @ sign in emails

Kenneth Thompson developed Unix

Linus Torvalds developed Linux

Tux – penguin mascot of the Linux kernel, based on an image created by Larry Ewing in 1996

The Whetstone benchmark primarily measures the floating-point arithmetic performance. A similar benchmark for integer and string operations is the Dhrystone

Cloud computing – using multiple server computers via a digital network, as though they were one computer

Duke – red-nosed mascot of Java

CAPTCHA is a type of challenge-response test used in computing as an attempt to ensure that the response is not generated by a computer

Malware – for 'malicious software', is any program or file that is harmful to a computer user

Hector (High End Computing Terascale Resources) is capable of 63 million million calculations a second and is four times faster than its predecessor

Crumb – 2 bits, nibble – 4 bits

A Trojan horse cannot replicate itself, but a virus can

APL is based on a mathematical notation developed by Kenneth E. Iverson

Sprite – a two-dimensional image or animation that is integrated into a larger scene

Rasterisation – the task of taking an image described in a vector graphics format (shapes) and converting it into a raster image (pixels or dots) for output on a video display or printer, or for storage in a bitmap file format

Decision support system (DSS) is a computer-based information system that supports business or organizational decision-making activities. DSSs include knowledge-based systems

Disc – optical storage device

Disk – magnetic storage device

Mosaic was developed at the National Center for Supercomputing Applications (NCSA) and released in 1993. First browser

RSA is an algorithm for public-key cryptography

Quantum computer – a device for computation that makes direct use of quantum mechanical phenomena, such as superposition and entanglement, to perform operations on data. Quantum computers are different from traditional computers based on transistors

In quantum computing, a qubit or quantum bit is a unit of quantum information

Shor's algorithm, named after mathematician Peter Shor, is a quantum algorithm for integer factorization formulated in 1994. It solves the following problem: Given an integer N, find its prime factors

Quantum cryptography is the use of quantum mechanical effects to perform cryptographic tasks or to break cryptographic systems, e.g. RSA

Ransomware comprises a class of malware which restricts access to the computer system that it infects, and demands a ransom paid to the creator of the malware in order for the restriction to be removed

Mouseover – a section of a computer user-interface that is raised when the user moves or hovers the pointer over a particular area of the GUI

Genetic algorithm – a search heuristic that mimics the process of natural selection

Neural networks – computational models inspired by animals' central nervous systems (in particular the brain) that are capable of machine learning and pattern recognition

Flash memory – an electronic non-volatile computer storage medium that can be electrically erased and reprogrammed

Blu-ray Disc refers to the blue laser used to read the disc, which allows information to be stored at a greater density than is possible with the longer-wavelength red laser used for DVDs

Holographic data storage records information throughout the volume of the medium and is capable of recording multiple images in the same area utilizing light at different angles

C was developed by Dennis Ritchie between 1969 and 1973 at AT&T Bell Labs

C++ was developed by Bjarne Stroustrup starting in 1979 at Bell Labs

Octothorp – # key (number sign or hash)

A multi-core processor is a single computing component with two or more independent actual central processing units (called cores’), e.g. dual-core and quad-core

Sasser is a computer worm that affects computers running vulnerable versions of Windows XP and Windows 2000. Sasser spreads by exploiting the system through a vulnerable network port

Stuxnet is a computer worm discovered in 2010. It initially spreads via Microsoft Windows, and targets Siemens industrial software and equipment. Different variants of Stuxnet targeted five Iranian organizations, with the probable target widely suspected to be uranium enrichment infrastructure in Iran

Helvetica is a widely used sans-serif typeface developed in 1957 by Swiss typeface designer Max Miedinger

Serif, or Roman, typefaces are named for the features at the ends of their strokes

In Microsoft Office 2007, Calibri replaced Times New Roman as the default typeface in Word and replaced Arial as the default in PowerPoint, Excel, and Outlook

Arial typeface was designed in 1982 by Robin Nicholas and Patricia Saunders for Monotype Typography

Times New Roman is a serif typeface commissioned by the newspaper, The Times, in 1931, designed by Stanley Morison and Victor Lardent at the English branch of Monotype

Lucida is an extended family of related typefaces designed by Charles Bigelow and Kris Holmes in 1985

Moore’s Law – the number of transistors that can be placed inexpensively on an integrated circuit doubles approximately every two years. The law is named after Intel co-founder Gordon E. Moore, who described the trend in his 1965

Turing machine – a device that manipulates symbols on a strip of tape according to a table of rules

Universal Turing machine – a Turing machine that can simulate an arbitrary Turing machine on arbitrary input

ICQ is an instant messaging computer program

A QR code (abbreviated from Quick Response code) is a type of matrix barcode first designed for the automotive industry. More recently, the system has become popular outside of the industry due to its fast readability and comparatively large storage capacity. The code consists of black modules arranged in a square pattern on a white background

Shannon-Hartley theorem says that there is always ‘noise’ getting in the way of accurate transmission of information. The aim is to keep the noise to a minimum, maintaining a high signal-to-noise ratio. The total amount of data that can be transmitted over a given time period is called the bandwidth

Banburismus was a cryptanalytic process developed by Alan Turing at Bletchley Park during the Second World War. It was used by Bletchley Park's Hut 8 to help break German messages enciphered on Enigma machines

The ban and the deciban were invented by Alan Turing with Jack Good in 1940, to measure the amount of information that could be deduced by the codebreakers at Bletchley Park using the Banburismus procedure

Reflected binary code, also known as Gray code after Frank Gray, is a binary numeral system where two successive values differ in only one bit. Gray codes are widely used to facilitate error correction in digital communications such as digital terrestrial television and some cable TV systems

LAMP – an acronym for an archetypal model of web service solution stacks, originally consisting of largely interchangeable components: Linux, the Apache HTTP Server, the MySQL relational database management system, and the PHP programming language

PHP is a server-side scripting language designed for web development. Created by Rasmus Lerdorf in 1994. While PHP originally stood for Personal Home Page, it now stands for PHP: Hypertext Preprocessor

World Wide Web

ARPANET (Advanced Research Projects Agency Network), created by the Defense Advanced Research Projects Agency (DARPA) of the United States Department of Defense, was the world's first operational packet switching network, and the predecessor of the contemporary global Internet. The packet switching of the ARPANET was based on designs by Lawrence Roberts, of the Lincoln Laboratory

The first Web site built ( was at CERN, and was first put on line on 6 August 1991

Information superhighway – often associated with the former Vice President of the United States, Al Gore, though the exact origins of the term are unknown

A country code top-level domain (ccTLD) is an Internet top-level domain generally used or reserved for a country

Video blogging, sometimes shortened to vlogging, is a form of blogging for which the medium is video and is a form of Web television

Cleverbot is a web application that uses an artificial intelligence algorithm to hold conversations with humans. Cleverbot took part alongside humans in a formal Turing Test in 2011

Among the earliest online comics were ‘Witches and Stitches’, which was published on CompuServe in 1985, and ‘T.H.E. Fox’, which was published on CompuServe and Quantum Link in 1986

Control Alt Delete, QC (Questionable Content) – web comics

The Whole Earth 'Lectronic Link, normally shortened to The WELL, is one of the oldest virtual communities in continuous operation. The WELL was started by Stewart Brand and Larry Brilliant in 1985

Ananova – first virtual newscaster

Cyberspace – virtual reality, the Internet, the World Wide Web, and other kinds of computer systems. Science-fiction author William Gibson coined the term in his novel Neuromancer

WikiLeaks is an international non-profit organisation that publishes submissions of private, secret, and classified media from anonymous news sources and news leaks. Its website, launched in 2006 under The Sunshine Press organisation, claimed a database of more than 1.2 million documents within a year of its launch

GhostNet – a large-scale cyber spying operation discovered in 2009. Its command and control infrastructure is based mainly in the People's Republic of China

The Million Dollar Homepage is a website conceived in 2005 by Alex Tew, a student from Wiltshire, to raise money for his university education. The home page consists of a million pixels arranged in a 1000 × 1000 pixel grid; the image-based links on it were sold for $1 per pixel

Mashable is an American news website and Internet news blog founded by Pete Cashmore

Jezebel is a blog aimed at women's interests, under the tagline ‘Celebrity, Sex, Fashion. Without Airbrushing’. It is one of several blogs owned by Gawker Media

xkcd is a webcomic created by Randall Munroe, a former contractor for NASA. Munroe describes it as ‘a webcomic of romance, sarcasm, math, and language’

Chatroulette is a online chat website that pairs strangers from around the world together for webcam-based conversations

The Spamhaus Project is an international organization founded in 1998 by Steve Linford to track email spammers and spam-related activity

BuzzFeed is a website that combines a technology platform for detecting viral content with an editorial selection process to provide a snapshot of ‘the viral web in realtime’

SETI@home is an Internet-based public volunteer computing project started in 1999. SETI@home searches for possible evidence of radio transmissions from extraterrestrial intelligence using observational data from the Arecibo radio telescope

Folding@home is a distributed computing project for disease research that simulates protein folding, computational drug design, and other types of molecular dynamics

Ethernet was developed at Xerox PARC between 1973 and 1974. It was inspired by ALOHAnet, which Robert Metcalfe had studied as part of his PhD dissertation

Dread Pirate Roberts is the founder and administrator of the illicit online marketplace the Silk Road, part of the internet’s dark net. The identity of Dread Pirate Roberts is kept hidden and the title may pass from one person to another, just as with the position's namesake in The Princess Bride novel by William Goldman

Tor (previously an acronym for The Onion Router) is free software for enabling online anonymity and censorship resistance. Tor directs Internet traffic through a free, worldwide, volunteer network consisting of more than five thousand relays to conceal a user's location or usage from anyone conducting network surveillance or traffic analysis

The Huffington Post is an American news website and aggregated blog founded by Arianna Huffington, Kenneth Lerer, and Jonah Peretti. Launched in 2005

Rotten Tomatoes was launched in 1999, as a spare time project by Senh Dong. The company is currently owned by Flixster, itself owned by Warner Bros since May 2011

Snopes is a web site that is the most widely-known resource for validating or debunking urban legends and Internet rumours

Tinder connects with users' Facebook profiles to provide pictures and ages for other users to view. Using GPS technology, users can set a specific radius. If two users like each other then it results in a match (double opt-in) and Tinder introduces the two users and opens a chat

Linden Lab – named after the street in San Francisco where the first office was situated

Anshe Chung (avatar of Ailin Graef) – Linden Lab millionaire, a virtual real estate broker. Founded by Philip Rosedale

Ask Jeeves – founded in 1996 by Garrett Gruener and David Warehen. dropped Jeeves in February 2006

Mumsnet is a community website set up by mothers to give advice on parenting and family issues. It was set up in 2000 by Justine Roberts and Carrie Longton

Airbnb is a website for people to rent out lodging. Founded in 2008 in San Francisco by Brian Chesky and Joe Gebbia

Weibo – Chinese version of Twitter

Phorm is a US company that offers a behavioral targeting advertisement service to monitor browsing habits and serve relevant advertisements to the end user

TMZ is a celebrity news website. The name TMZ stands for ‘thirty-mile zone’, the historic ‘studio zone’ within a 30-mile radius centered on Los Angeles

Favicon – (short for Favourite icon) is a file containing one or more small icons associated with a particular Web site or Web page

CYCLADES packet switching network was a French research network created in the early 1970s. It was developed to explore alternatives to the ARPANET design and to support network research generally

Vinton Gray ‘Vint’ Cerf  is an American Internet pioneer, who is recognized as one of ‘the fathers of the Internet’, sharing this title with Bob Kahn, for the invention of TCP/IP

Snapchat is a photo messaging application developed by Evan Spiegel, Bobby Murphy, and Reggie Brown, then Stanford University students. Using the application, users can take photos, record videos, add text and drawings, and send them to a controlled list of recipients. These sent photographs and videos are known as "Snaps". Users set a time limit for how long recipients can view their Snaps

Shazam is a commercial mobile phone based music identification service. Shazam uses a mobile phone's built-in microphone to gather a brief sample of music being played. An acoustic fingerprint is created based on the sample, and is compared against a central database for a match


Analog electronics – electronic systems with a continuously variable signal

Capacitor (formerly known as condenser) is a passive electronic component consisting of a pair of conductors separated by a dielectric (insulator). When a potential difference (voltage) exists across the conductors, an electric field is present in the dielectric. This field stores energy and produces a mechanical force between the conductors

A charge-coupled device (CCD) is a device for the movement of electrical charge, usually from within the device to an area where the charge can be manipulated, for example conversion into a digital value. The CCD is a major technology for digital imaging. Allows satellites to store images and send them back to Earth as radio waves

A cat’s whisker detector (sometimes called a crystal detector) is an antique electronic component consisting of a thin wire that lightly touches a crystal of semiconducting mineral to make a crude point-contact rectifier. This device was used as the detector in early crystal radios

Components connected in series are connected along a single path, so the same current flows through all of the components. Components connected in parallel are connected so the same voltage is applied to each component

A flip-flop or latch is a circuit that has two stable states and can be used to store state information

Digital electronics represent signals by discrete bands of analog levels, rather than by a continuous range

Diode – device that allows current to flow in one direction only. Diode is the simplest vacuum tube

Integrated circuit – a set of electronic circuits on one small plate (‘chip’) of semiconductor material, normally silicon

Inverter – a device that converts DC to AC

Light-emitting diode (LED) – a semiconductor diode that converts applied voltage to light

Logic gate – a device implementing a Boolean function; that is, it performs a logical operation on one or more logical inputs, and produces a single logical output

Types of logic gate – AND, OR, NOT, NAND, NOR, XOR (output is 1 if inputs are different), XNOR (inverse of XOR)

Most Boolean logic gates can be created from a suitable network of NAND gates

Photodiode – a semiconductor capable of converting light into either current or voltage

Resistor – an electronic component that restricts the flow of current in an electrical or electronic circuit

Resistors in series – add values to get overall resistance R = R1 + R2 + R3...

Resistors in parallel – 1/R = 1/R1 + 1/R2 + 1/R3...

Rheostat – a continuously variable electrical resistor used to regulate current

Semiconductor – a substance as germanium or silicon whose electrical conductivity is intermediate between that of a conductor and an insulator

n-type semiconductor – a semiconductor in which electrical conduction is due chiefly to the movement of electrons

p-type semiconductor – a semiconductor in which electrical conduction is due chiefly to the movement of positive holes

In semiconductor production, doping is the process of intentionally introducing impurities into an extremely pure (also referred to as intrinsic) semiconductor to change its electrical properties. The impurities are dependent upon the type of semiconductor. Lightly and moderately doped semiconductors are referred to as extrinsic. A semiconductor doped to such high levels that it acts more like a conductor than a semiconductor is referred to as degenerate

Thermistor – an electrical resistor whose resistance is greatly reduced by heating

Transistor – a semiconductor device used to amplify and switch electronic signals

Bipolar and Field Effect – major types of transistor

Thyristor – a four-layered semiconductor rectifier in which the flow of current between two electrodes is triggered by a signal at a third electrode. Used in dimmer switches

Thyristor – a solid-state semiconductor device with four layers of alternating N and P-type materials

Triode – an electronic amplifying vacuum tube (valve) which consists of three electrodes inside an evacuated glass envelope: a heated filament or cathode, a grid, and a plate (anode)

A vacuum tube, electron tube, or thermionic valve (reduced to simply ‘valve’), is a device that relies on the flow of electric current through a vacuum. Vacuum tubes rely on thermionic emission of electrons from a hot filament or hot cathode, that then travel through a vacuum toward the anode (commonly called the plate), which is held at a positive voltage relative to the cathode. Additional electrodes interposed between the cathode and anode can alter the current, giving the tube the ability to amplify and switch

Mobile phones

The first hand-held cell phone was demonstrated by John F. Mitchell and Dr. Martin Cooper of Motorola in 1973, using a handset weighing around 2 kg. In 1983, the DynaTAC 8000x was the first to be commercially available. From 1983 to 2014, worldwide mobile phone subscriptions grew from zero to over 7 billion

It was claimed that Ernie Wise made the first mobile phone call in the UK on 1 January 1985 from St Katharine Docks, East London, to Vodafone's Headquarters in Newbury

The first SMS text message was sent from a computer to a mobile phone in 1992 in the UK, while the first person-to-person SMS from phone to phone was sent in Finland in 1993.

The first mobile news service, delivered via SMS, was launched in Finland in 2000

The first SIM card was made in 1991 by Munich smart card maker Giesecke & Devrient

GSM (Global System for Mobile Communications) is a standard developed by the European Telecommunications Standards Institute (ETSI) to describe protocols for second-generation (2G) digital cellular networks used by mobile phones. As of 2014[update] it has become the default global standard for mobile communications

Universal Mobile Telecommunications System (UMTS) is a third generation mobile cellular system for networks based on the GSM standard

Symbian – operating system used in Nokia phones. It was the most popular smartphone OS on a worldwide average until the end of 2010, when it was overtaken by Android

Demand for metals found in mobile phones and other electronics fuelled the Second Congo War

In 2014, the top cell phone manufacturers were Samsung, Nokia, Apple, and LG

The world's largest individual mobile operator by subscribers is China Mobile with over 500 million mobile phone subscribers

Video recorders

The videocassette recorder, VCR, or video recorder, records analog audio and analog video from broadcast television or other source on a removable, magnetic tape videocassette

Ampex introduced the Quadruplex videotape professional broadcast standard format with its Ampex VRX-1000 in 1956. It became the world's first commercially successful videotape recorder

In 1959 Toshiba announced a new method of recording known as helical scan, first implemented in reel-to-reel videotape recorders (VTRs)

The Telcan, produced by the UK Nottingham Electronic Valve Company in 1963, was the first home video recorder

The Sony model CV-2000, first marketed in 1965, was their first VTR intended for home use

In the 1970s, JVC’s VHS (Video Home System) won the ‘Videotape format war’ against Sony’s Betamax and Philip’s V2000

DVD rentals in the United States first exceeded those of VHS in 2003

The High definition optical disc format war was between the Blu-ray Disc and HD DVD optical disc standards for storing high definition video and audio; it took place between 2006 and 2008 and was won by Blu-ray Disc


Acorn Computers was founded in 1978 by Hermann Hauser and Chris Curry. Produced the Acorn Electron and BBC Micro (1981)

Adobe Systems – Photoshop was created by Thomas Knoll and John Knoll

Alibaba Group was founded in 1999 by Jack Ma with the web site

Amazon was incorporated in 1994, in the state of Washington. In 1995, the company began service and sold its first book on – Douglas Hofstadter’s Fluid Concepts and Creative Analogies: Computer Models of the Fundamental Mechanisms of Thought

Amazon was founded by CEO Jeff Bezos in 1994

Amazon Kindle is an electronic book (e-book) device launched in the United States by in 2007. It uses an electronic paper display, reads the proprietary Kindle (AZW) format, and downloads content over Amazon Whispernet, which uses the Sprint EVDO network

Apple was founded by Steve Jobs, Steve Wozniak, and Ronald Wayne on 1 April 1976, to develop and sell personal computers. It was incorporated as Apple Computer, Inc. in 1977, and was renamed as Apple Inc. in 2007, to reflect its shifted focus towards consumer electronics

The Apple I went on sale in July 1976 and was market-priced at $666.66

VisiCalc created a business market for the Apple II

Apple Lisa was released in 1983

Apple Mac was introduced by Steve Jobs in 1984. Its debut was signified by 1984, a $1.5 million television commercial modeled after the George Orwell novel and directed by Ridley Scott, that aired during the 1984 Super Bowl

iMac was the first PC sold without a floppy drive

iMac is a range of all-in-one Macintosh desktop computers built by Apple. It has been the primary part of Apple's consumer desktop offerings since its introduction in 1998, and has evolved through five distinct forms

Newton platform was an early personal digital assistant and the first tablet platform developed by Apple, the second platform being iOS, used in the iPhone, iPod Touch and iPad. Development of the Newton platform started in 1987 and ended in 1998

iMac and iPod designed by Jonathan Ive

Ipod nano (2005), shuffle (2005), touch (2007), classic (2007)

iPhone 4S has a voice recognizing and talking assistant called Siri

John Sculley was president of PepsiCo (1977–83), until he became CEO of Apple in 1983, a position he held until leaving in 1993

iCloud allows users to store data such as music files for download to multiple devices such as iPhones, iPods, iPads, and personal computers running Mac OS X or Microsoft Windows on computer servers owned by Apple

Retina Display is a brand name used by Apple for liquid crystal displays which they claim have a high enough pixel density that the human eye is unable to notice pixelation at a typical viewing distance

Tim Cook – CEO of Apple

Apple's worldwide annual revenue in 2014 totaled US$182 billion

Safari is the default web browser for iPad

ARM Holdings is market dominant in the field of mobile phone chips. Based in Cambridge. The company was founded as Advanced RISC Machines, ARM, a joint venture between Acorn Computers, Apple Computer and VLSI Technology is an online-only fashion and beauty store. Revenue in 2012 was £495 million

BlackBerry Limited, formerly known as Research In Motion Limited (RIM), is a Canadian telecommunication and wireless equipment company founded by Mike Lazaridis. BlackBerry Bold family was launched in 2008

Bebo – online social networking site. Founded in 2005 by Michael and Xochi Birch. In 2013, the company voluntarily filed for Chapter 11 bankruptcy protection was a British Internet company, founded by three Swedes, which went bust following the dot-com boom of the late 1990s. The company spent $135 million of venture capital in just 18 months, and it was placed into receivership in 2000 and liquidated

Bwin.Party Digital Entertainment is an online gambling company. The world's largest publicly traded online gambling firm, it is best known for its online poker room Bwin sponsored Real Madrid, AC Milan and Bayern Munich and more recently Olympique de Marseille

Cisco Systems was founded in 1984 by Leonard Bosack, who was in charge of the Stanford University computer science department's computers, and Sandy Lerner. John Chambers has been chairman and CEO since 1995

Compaq was founded by Rob Canion. Acquired by Hewlett-Packard in 2002

Craigslist is a centralized network of online communities, featuring free classified advertisements. The service was founded in 1995 by Craig Newmark for the San Francisco Bay Area

eBay was founded by Pierre Omidyar in 1996. Would have been called, had the domain name not already been taken. One of the first items sold on AuctionWeb (earlier web sirte created by Omidyar) was a broken laser pointer for $14.83. John Donahoe is CEO of eBay

Facebook Mark Zuckerberg – CEO of Facebook, which he founded while attending Harvard

Sheryl Sandberg – Chief Operating Officer of Facebook

In 2006, Facebook launched News Feed, a product to show what your friends were doing on the site

Yahoo! offered $1 billion for Facebook in 2006

Microsoft offered $15 billion for Facebook in 2007

Winkelvoss twins received $65 million in settlement from Facebook in 2008

Facebook Home is a user interface layer for Android-compatible smartphones

Facemash – predecessor to Facebook

Sponsored Stories are posts from your friends or Pages on Facebook that a business, organization or individual has paid to highlight

Flickr is an image and video hosting website, web services suite, and online community. Flickr was developed by Ludicorp, a Vancouver-based company that launched Flickr in February 2004

Foxconn, based in Taiwan, is the world's largest maker of electronic component including printed circuit boards

GoDaddy is the largest domain name registration company in the world

Google was founded in 1998 by Larry Page and Sergey Brin while they were Ph.D. students at Stanford University

HQ in Mountain View, California

Googlefight is a website that allows users to compare the number of search results returned by the Google search engine for two given queries

Android – a software stack for mobile devices that includes an operating system, middleware and key applications that uses a modified version of the Linux kernel

Android is a mobile operating system initially developed by Android Inc. Android was bought by Google in 2005

AdWords is Google's flagship advertising product and main source of revenue.AdWords offers pay-per-click (PPC) advertising, and site-targeted advertising for both text and banner ads

Google was originally known as Backrub

Google Earth is a virtual globe program that was originally called Earth Viewer and was created by Keyhole, Inc. It maps the earth by the superimposition of images obtained from satellite imagery, aerial photography and GIS over a 3D globe. It is available under three different licenses: Google Earth, a free version with limited functionality; Google Earth Plus, which includes a few more features; and Google Earth Professional, intended for commercial use

Google Street View is a feature of Google Maps and Google Earth that provides for many streets in the world 360° horizontal and 290° vertical panoramic views

*Google+ (pronounced and sometimes written as Google Plus, sometimes abbreviated as G+) is a social networking and identity service

Google Glass is a wearable computer with a head-mounted display (HMD) that is being developed by Google in the Project Glass research and development project

Changing Google logo is known as the Google Doodle

Larry Page – CEO of Google

Eric Schmidt – Executive chairman of Google

Groupon (a portmanteau derived from ‘group coupon’) is a deal-of-the-day website that features discounted gift certificates usable at local or national companies. Groupon was launched in 2008, the first market for Groupon was Chicago. The idea for Groupon was created by now-CEO Andrew Mason

Hewlett-Packard bought Palm in 2010 for $1.2 billion. Meg Whitman – CEO of Hewlett-Packard

IBM. The Computing Tabulating Recording Company became IBM in 1924

Virginia Rometty – CEO of IBM

IMDb originated from a list started as a hobby by film enthusiast Col Needham (founder and CEO of IMDb) in 1989

Intel – Integrated Electronics, founded in 1968. Purchased McAfee in 2011

Instagram was created by Kevin Systrom and Mike Krieger and launched in 2010

Just Eat is an online takeaway food delivery service, headquartered in the UK and operating in 13 countries. Founded in 2000 in Denmark. Floated on the London Stock Exchange in 2014

Kaspersky Lab is a Russian computer security company, co-founded by Natalia Kaspersky and Eugene Kaspersky in 1997, offering anti-virus, anti-spyware, anti-spam, and anti-intrusion products is a casual-social games company, and the largest game developer on Facebook. Games include Candy Crush Saga

Lenovo is China’s largest PC manufacturer. Formerly the PC branch of IBM

LinkedIn was founded by Reid Hoffman in 2002

Microsoft was founded in 1975 in Albuquerque by Bill Gates and Paul Allen. HQ is now in Redmond, Washington

Bing – Microsoft web search engine

Kinect for Xbox 360 is a ‘controller-free gaming and entertainment experience’. Based around a webcam-style add-on peripheral for the Xbox 360 console, it enables users to control and interact with the Xbox 360 without the need to touch a game controller, through a natural user interface

Start Me Up – used to advertise Windows 95

Bing Map is a web mapping service provided as a part of Microsoft's Bing suite of search engines

Satya Nadella – CEO of Microsoft

Mind Candy is a British entertainment company, formed in 2004 by UK internet entrepreneur Michael Acton Smith. Moshi Monsters is a website developed by Mind Candy aimed at children aged 6–14 with over 87 million registered users worldwide. Users choose from one of six virtual pet monsters. Players navigate their way around Monstro City

MySpace was founded by Tom Anderson. Rupert Murdoch paid $580 million to buy MySpace in 2005

Napster was an online music file sharing service created by Shawn Fanning while he was attending Northeastern University in Boston. The service operated between June 1999 and July 2001. Opposed by Metallica

Net-a-Porter is a high-fashion retailer that operates via a website designed in the style of a magazine

Netflix was founded in 1997 in Scotts Valley, California by Marc Randolph and Reed Hastings. Netflix has subscribers in over 40 countries

NeXT was founded in 1985 by Steve Jobs after he was fired from Apple the same year. NeXT introduced the first NeXT Computer in 1988. Apple purchased NeXT in 1996

PayPal was co-founded by Elon Musk in 1998. Bought by eBay in 2002

Photobucket is an image hosting, video hosting, slideshow creation and photo sharing website. It was founded in 2003 by Alex Welch and Darren Crystal

Reddit is a collection of entries submitted by its registered users, essentially a bulletin board system. Founded by Steve Huffman and Alexis Ohanian in 2005

SanDisk Corporation, formerly SunDisk, is an American multinational corporation which designs and markets flash memory card products. SanDisk was founded in 1988 by Eli Harari and Sanjay Mehrotra

Sinclair Executive was Clive Sinclair's first venture into the pocket calculator market. Launched in 1972

Sinclair Cambridge calculator was launched in 1973

Sinclair ZX Spectrum was released in 1982

Sinclair C5 was a small one-person battery electric vehicle, introduced in 1985 at a cost of £399. Out of 14,000 C5s made, only 5,000 were sold before its manufacturer, Sinclair Vehicles, went into receivership

Skype is a peer-to-peer Internet telephony network founded by the entrepreneurs Niklas Zennstrom and Janus Friis, also founders of the file sharing application KaZaA and free internet venture Joost

Sporcle was founded bt Matt Ramme in 2007

Spotify was founded in 2006 by Daniel Ek and Martin Lorentzon. Spotify – a proprietary peer-to-peer music streaming service that allows instant listening to specific tracks or albums with almost no buffering delay

Telegram was founded in 2013 by the brothers Nikolai and Pavel Durov, the founders of VK, Russia's largest social network

TripAdvisor was founded in 2000 by Stephen Kaufer

Twitter was created in 2006 by Jack Dorsey, Evan Williams, Biz Stone and Noah Glass

Video app Vine allows users to record and share six-second clips

Maximum length of a tweet is 140 characters

Dick Costolo – CEO of Twitter

As of December 2013[update], Twitter had a market capitalization of $32 billion

As of July 2014, Twitter has more than 500 million users, out of which more than 271 million are active users

Vine lets users record and edit up to six-second-long looping video clips and revine, or share others' posts with followers. Owned by Twitter

Tumblr is a microblogging platform and social networking website. Founded by David Karp in 2007. Sold to Yahoo! in 2013

Webvan was an online ‘credit and delivery’ grocery business that went bankrupt in 2001. It was headquartered in Foster City, California

Wikipedia was founded by Jimmy Wales in 2001

Wikimedia Foundation – parent company of Wikipedia

Wikivoyage travel guide was launched in 2012

With 18 billion page views and nearly 500 million unique visitors a month, Wikipedia trails just Yahoo, Facebook, Microsoft and Google, the largest with 1.2 billion unique visitors was founded by Errol Damelin and Jonty Hurwitz in 2007

Yahoo! Was founded by David Filo and Jerry Yang, in 1995

Marissa Mayer – CEO of Yahoo!

YouGov is a British internet-based market research firm. It was launched in 2000 by Stephan Shakespeare (CIO) and Nadhim Zahawi (CEO)

YouTube. The first YouTube video was entitled Me at the zoo, and shows Jawed Karim at the San Diego Zoo. The video was uploaded on April 23, 2005

YouTube was created in 2005 by three former PayPal employees – Steve Chen, Chad Hurley and Jawed Karim