What improvements have been made to the telephone over the past 100 years?

In the years inventors have improved the telephone with their knowledge and have put more technology in them.In the years inventors have improved the telephone with their knowledge and have put more technology in them.In the years inventors have improved the telephone with their knowledge and have put more technology in them.In the years inventors have improved the telephone with their knowledge and have put more technology in them.In the years inventors have improved the telephone with their knowledge and have put more technology in them.In the years inventors have improved the telephone with their knowledge and have put more technology in them.In the years inventors have improved the telephone with their knowledge and have put more technology in them.In the years inventors have improved the telephone with their knowledge and have put more technology in them.In the years inventors have improved the telephone with their knowledge and have put more technology in them.In the years inventors have improved the telephone with their knowledge and have put more technology in them.In the years inventors have improved the telephone with their knowledge and have put more technology in them.In the years inventors have improved the telephone with their knowledge and have put more technology in them.In the years inventors have improved the telephone with their knowledge and have put more technology in them.In the years inventors have improved the telephone with their knowledge and have put more technology in them.