Analogue: a mobile phone system, using the 088 prefix. It sends radio signals which can easily be monitored by anyone with the right equipment. Expected to become obsolete as a system within a decade.

GSM: known as the Global System for Mobiles, it uses the more efficient digital rather than analogue signals. In Ireland the system uses the 086 or 087 prefix and is generally secure from eavesdroppers.

UTMS: known as the third generation of mobile phones or Universal Mobile Telecommunications Systems (UMTS), will provide far faster data throughput rates.

It is expected that users will be able to use their phones for a huge number of transactions ranging from booking seats for air travel to downloading information from various sources.

E-mail: sending messages from one computer to another, either through the Internet or on a local system.