Telephones

The telephone or phone (Greek: tele = far away and phone = voice) is a telecommunications device which is used to transmit and receive sound (most commonly voice and speech) across distance. more...

Most telephones operate through transmission of electric signals over a complex telephone network which allows almost any phone user to communicate with almost any other.

Introduction

There are four principal means by which an end user using a telephone handset may connect to a telephone network: a traditional fixed phone "landline", which uses dedicated physical wire connections connected to a single location; wireless and radio telephones, which use either analog or digital radio signals; satellite telephones, which utilize telecommunications satellites; and voice over internet protocol (VoIP) telephones, which use broadband internet connections.

Between end users, transmissions across a network may be carried by fiber optic cable, point to point microwave or satellite relay.

Until relatively recently, a "telephone" generally referred only to landlines. Cordless and mobile phones are now common in many places around the world, with mobile phones expected to gradually displace the conventional landline telephone. Unlike a mobile phone, a cordless telephone is considered to be landline because it is only useable within a short distance of a small personal or domestic base station connected to a fixed phone line.

The identity of the inventor of the electric telephone remains in dispute. Antonio Meucci, Johann Philipp Reis, and Alexander Graham Bell, amongst others, have all been credited with the invention.

History

The very early history of the telephone is a confusing morass of claim and counterclaim, which was not clarified by the huge mass of lawsuits which hoped to resolve the patent claims of individuals. There was a lot of money involved, particularly in the Bell Telephone companies, and the aggressive defense of the Bell patents resulted in much confusion. Additionally, the earliest investigators preferred publication in the popular press and demonstration to investors instead of scientific publication and demonstration to fellow scientists.

It is important to note that there is probably no single "inventor of the telephone". The modern telephone is the result of work done by many hands, all worthy of recognition of their addition to the field.

Further information: Timeline of the telephone, and Invention of the telephone, and , and , and , and , and , and , and

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