Description: The first telephone system, known as an exchange, which is a practical means of communicating between many people who have telephones, was installed in Hartford, Connecticut in 1877, and the first ex-change linking two major cities was established between New York and Boston in 1883. The first exchange outside the United States was built in London in 1879. The exchange involved a group of operators working at a large switchboard who would answer an incoming telephone call and connect it manually to the party being called. The first automatic telephone exchange was patented by Almon Strowger of Kansas City in 1891 and installed in 1892, but manual switchboards remained in common use until the middle of the twentieth century. (information from www.ideafinder.com)