A mobile or cell(ular) (tele)phone
is a long-range, portable electronic device for
peer-to-peer telecommunications over long distances.
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 are satellite phones). Cellular
networks were first introduced in the early to mid 1980s
(the 1G generation). Prior mobile phones operating
without a cellular network (the so-called 0G
generation), such as Mobile Telephone Service, date back
to 1945. Until the mid to late 1980s, most mobile phones
were sufficiently large that they were permanently
installed in vehicles as car phones. With the advance of
miniaturization, currently the vast majority of mobile
phones are handheld. In addition to the standard voice
function of a telephone, a mobile phone 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.
The world's largest mobile phone manufacturers include
Audiovox, BenQ-Siemens, High Tech Computer Corporation,
Fujitsu, Kyocera, LG, Motorola, NEC, Nokia, Panasonic
(Matsushita Electric), Pantech Curitel, Philips, Sagem,
Samsung, Sanyo, Sharp, SK Teletech, Sony Ericsson,
T&A Alcatel and Toshiba.
The world's largest mobile phone operators include
Orange SA, China Mobile and Vodafone.
There are also specialist communication systems related
to, but distinct from mobile phones, such as
Professional Mobile Radio. Mobile phones are also
distinct from cordless telephones, which generally
operate only within a limited range of a specific base
station. Technically, the term mobile phone includes
such devices as satellite phones and pre-cellular mobile
phones such as those operating via MTS which do not have
a cellular network, whereas the related term cell(ular)
phone does not. In practice, the two terms are used
nearly interchangeably, with the preferred term varying
by location.
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