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Cellular telephones perform the same functions as an ordinary telephone. They can be used for instant voice communications with another person. By dialling the number of another cellular telephone you can instantly talk to the person who owns it. Over 30 million cellular telephones have been sold in the UK.
Ordinary telephones are connected to the telephone network by cables which run under and above the ground. Because of this a telephone can not be moved around. It can only be used near the point at which it connects to the network. In contrast a cellular telephone connects to the telephone network using radio waves. A cellular phone can be moved around and used at any point that is covered by the network. Most cellular phones can be used anywhere within the country they are purchased in and can often be used abroad as well.
Data can be transmitted using a modem and a cellular phone but this transmission is much slower than sending data with an ordinary phone. You can send text messages from one cellular phone to another using a system called Simple Messaging System (SMS). WAP phones let you access some Internet sites so that you can get useful text information such as traffic news via your phone. More similar services will be introduced now that faster GPRS phones are available.
There are many different ways that you can pay to use a cellular phone. Whichever way you choose, it is normally more expensive to use a cellular phone than an ordinary phone. There is a continuing debate over the safety of cellular telephones. Some surveys suggest that the radiowaves transmitted and received by these phones might affect brain activity.
Advantages
Disadvantages
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GCSE ICT Companion 04 - (C) P Meakin 2004