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The mobile phone or cell phone is a long-range,
portable electronic device used for mobile communication. In
addition to the standard voice function of a telephone, current
mobile phones can support many additional services such as SMS for
text messaging, email, packet switching for access to the Internet,
and MMS for sending and receiving photos and video. Most current
mobile phones connect to a cellular network of base stations (cell
sites), which is in turn interconnected to the public switched
telephone network (PSTN) (the exception is satellite phones).  
There is one U.S. patent, Patent Number 887357 for a wireless
telephone, issued 1908 to Nathan B. Stubblefield of Murray,
Kentucky. He applied this to "cave radio" telephones and not
directly to cellular telephony as we know it today.However, the
introduction of cells for mobile phone base stations, invented in
1947 by Bell Labs engineers at AT&T, was further developed by Bell
Labs during the 1960s. Radiophones have a long and varied history
going back to Reginald Fessenden's invention and shore-to-ship
demonstration of radio telephony, through the Second World War with
military use of radio telephony links and civil services in the
1950s, while hand-held cellular radio devices have been available
since 1983. Due to their low establishment costs and rapid
deployment, mobile phone networks have since spread rapidly
throughout the world, outstripping the growth of fixed
telephony.
 
In 1945, the zero generation (0G) of mobile telephones was
introduced. 0G mobile telephones, such as Mobile Telephone Service,
were not officially categorized as mobile phones, since they did not
support the automatic change of channel frequency during calls,
which allows the user to move from one cell (the base station
coverage area) to another cell, a feature called "handover".[citation
needed]
In 1984, Bell Labs invented such a "call handoff" feature, which
allowed mobile-phone users to travel through several cells during
the same conversation. Motorola is widely considered to be the
inventor of the first practical mobile phone for handheld use in a
non-vehicle setting. Using a modern, if somewhat heavy portable
handset, Motorola manager Martin Cooper made the first call on a
handheld mobile phone on April 3, 1973.[2]
 
The first commercial cellular network was launched in Japan by NTT
in 1979. Fully automatic cellular networks were first introduced in
the early to mid 1980s (the 1G generation) with the Nordic Mobile
Telephone (NMT) system in 1981. This was followed by a boom in
mobile telephone usage, particularly in Northern Europe.[citation
needed]
The first "modern" network technology on digital 2G (second
generation) cellular technology was launched by Radiolinja (now part
of Elisa Group) in 1991 in Finland on the GSM standard which also
marked the introduction of competition in mobile telecoms when
Radiolinja challenged incumbent Telecom Finland (now part of
TeliaSonera) who ran a 1G NMT network. A decade later, the first
commercial launch of 3G (Third Generation) was again in Japan by NTT
DoCoMo on the WCDMA standard.[citation needed] Until the early
1990s, most mobile phones were too large to be carried in a jacket
pocket, so they were typically installed in vehicles as car phones.
With the miniaturization of digital components, mobile phones have
become increasingly handy over the year
 
Manufacturers
The mobile phone manufacturers can be grouped into two. The top five
are available in practically all countries and comprise about 75% of
all phones sold. A second tier of small manufacturers exists with
phones mostly sold only in specific regions or for niche markets.
The top five in order of market share are Nokia, Motorola, Samsung,
SonyEricsson and LG.
Nokia Corporation is currently the world's largest manufacturer of
mobile telephones, with a global device market share of
approximately 36% in Q1 of 2007.[3] Other mobile phone manufacturers
include Apple Inc., Audiovox (now UT Starcom), Benefon, BenQ-Siemens,
High Tech Computer Corporation (HTC), Fujitsu, Kyocera, LG Mobile,
Mitsubishi, Motorola, NEC, Neonode, Panasonic (Matsushita Electric),
Pantech Curitel, Philips, Research In Motion, Sagem, Samsung, Sanyo,
Sharp, Siemens, Sierra Wireless, SK Teletech, Sonim Technologies,
Sony Ericsson, T&A Alcatel,Toshiba, and Verizon. There are also
specialist communication systems related to (but distinct from)
mobile phones.
 
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