1.1. Introduction

The word telecommunication was adapted from the French word télécommunication. It is a compound of the Greek prefix tele, meaning 'far off', and the Latin communicare, meaning 'to share'. The French word télécommunication was coined in 1904 by French engineer and novelist Édouard Estaunié. Telecommunication is the transmission of signals over a distance for the purpose of communication. In earlier times, this may have involved the use of smoke signals, drums, semaphore, flags or heliograph. In modern times, telecommunication typically involves the use of electronic devices such as telephones, television, radio or computers. Early inventors in the field of telecommunication include Alexander Graham Bell, Guglielmo Marconi and John Logie Baird. Telecommunication is an important part of the world economy and the telecommunication industry's revenue was estimated to be $1.2 trillion in 2006.