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JPEG (usually pronounced JAY-pehg) is a term for any graphic image file produced by using a JPEG standard.

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Also known as: First Generation 1G (First Generation) is the name given to the first generation of mobile telephone networks. These systems used analogue circuit-switched technology, with FDMA (Frequency Division Multiple Access), and worked mainly in the 800-900 MHz frequency bands. The networks had a low traffic capacity, unreliable handover, poor voice quality, and poor security. As the 1G networks became obsolete, their frequencies were auctioned off for use in 2G and 3G networks. Examples of these first generation mobile phone networks are AMPS (Advanced Mobile Phone Service), TACS/ETACS (Total Access Communications System / Extended Total Access Communications System), NMT 450 (Nordic Mobile Telephone System) and NTT (Nippon Telegraph and Telephone System).
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Also known as: Second Generation 2G (Second Generation) is the generic term used to refer to the second generation of wireless mobile telephone networks, which were the first to feature purely digital technology. As demands for the quality and quantity of mobile communication services increased, 2G systems were the logical next stage in the evolution from the 1G (first generation) analogue systems. Typical characteristics of 2G include roaming, better high-bit-rate voice quality, improved security with different levels of encryption, the ability to convey some data (e.g. SMS) as well as speech, and a wider selection of subscriber services. Examples of the major second generation digital mobile telephony systems are: GSM (Global System for Mobile Communications) in Europe, IS-95 (CDMAone) and IS-136 (D-AMPS / TDMA) in the USA, and PDC (Personal Digital Cellular) in Japan
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Also known as: Second Generation 2G (Second Generation) is the generic term used to refer to the second generation of wireless mobile telephone networks, which were the first to feature purely digital technology. As demands for the quality and quantity of mobile communication services increased, 2G systems were the logical next stage in the evolution from the 1G (first generation) analogue systems. Typical characteristics of 2G include roaming, better high-bit-rate voice quality, improved security with different levels of encryption, the ability to convey some data (e.g. SMS) as well as speech, and a wider selection of subscriber services. Examples of the major second generation digital mobile telephony systems are: GSM (Global System for Mobile Communications) in Europe, IS-95 (CDMAone) and IS-136 (D-AMPS / TDMA) in the USA, and PDC (Personal Digital Cellular) in Japan
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Also known as: Conference Call 3-Way Calling (Conference Call) is a network facility that enables three or more parties to be connected together in a conference call, so that they may all speak and listen simultaneously. This is often used as a convenient substitute for a physical meeting, as the participants can be located in different towns, or even in different countries. This feature is very useful when two friends are having a conversation and they need to ask questions of a third person instead of hanging up and calling back, the third party can be dialled during the course of the conversation to set up a conference call
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Also known as: Third Generation 3G (Third Generation) is a generic term used to refer to the latest standard of wireless mobile telephone networks. Third Generation phones are capable of the high data rates, wide bandwidth and increased capacity needed to support the new range of digital services available for mobile devices, such as Internet access, multimedia applications, and support for global roaming. The major multiple access transmission technique used in 3G is CDMA, a packet-switching technology, which provides a more efficient use of the available spectrum than did the earlier methods of FDMA and TDMA. The two main 3G technologies used are UMTS with wideband CDMA (W-CDMA) in Europe, and cdma2000™ with multi-carrier CDMA (MC-CDMA) in the USA. Many 3G systems will operate in the 2 GHz frequency band, and are designed to provide a range of data rates from 144 kbps to 2 Mbps, depending on the user's location and circumstances. The 3G mobile communications standard was a programme led originally by the ITU under the IMT-2000 project, and handsets and networks are now generally defined as UMTS (Universal Mobile Telecommunication Service). However, despite the intention that the IMT-2000 specification would result in a single, unified 3G system, several different versions of 3G have developed due to the leading telecommunications companies choosing to take a more evolutionary approach to upgrading their networks
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