British Telecom is the oldest telecommunications company in the world. Since 1984 it has been a private company and has become a global leader in all aspects of communication as well as one of the UK's most profitable companies.
As BT evolved from a state monopoly it easily held onto its status as the main provider of telephones for the home. They used to supply phone as part of your contract, though nowadays many people buy their landline phones from the HIgh Street of from Online stores.
BT is also a major player in many other industries including broadband, business telephone systems and ( via their now separate outlet ) O2 mobiles who are proud to be the carrier of the iPhone in the UK.
BT have a large range of telephones aimed at allowing the differently abled to access its communications network with the same ease as others.