Fibre optic cables are similar to the fibre optic used in some Christmas trees
They carry light down them and can be used to transmit broadband data. They can send data a lot faster than ordinary copper telephone cabling that BT use.
BT are working on a project to install fibre optic cables to be with the exisitng wiring from the exchanges to the phone cabinets that are situated on the roads near people's houses. This is going to take several years and they do exchange by exchange.
It will have little effect on you, apart from road works. Once your exchange is upgraded then you could if you wish sign up to use fibre optic broadband in place of the current copper cabling broadband. It would be faster but you would have to pay more. There would be no effect on your telephone as such, though it might improve reception.
Virgin broadband uses fibre optic cable. The difference is that with BT, the fibre optic cable stops at the phone cabinets, then the exisiting copper cabling carries on between those and your router, thus there must be some loss of speed but not hugh), but with Virgin, it's optic all the way to your router,
