A mobile phone is a device which behaves as a normal telephone whilst being able to move over a wide area (cf. cordless phone which acts as a telephone only within a limited range). Mobile phones allow connections to be made to the telephone network, normally by directly dialling the other party's number on an inbuilt keypad. Most current mobile phones use a combination of radio wave transmission and conventional telephone circuit switching, though packet switching is already in use for some parts of the mobile phone network, especially for services such as internet access and WAP.
Mobile phone manufacturers include Audiovox, Kyocera (formerly the handset division of Qualcomm), Motorola, Nokia, Panasonic (Matsushita Electric), Samsung, Sanyo, Siemens, Sony Ericsson, Alcatel, LG and Sagem.
There are also specialist communication systems related to, but distinct from mobile phones, such as satellite phones and Professional Mobile Radio.
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