Philadelphia already had mail links to surrounding towns and to Maryland and Virginia by 1737, when Benjamin Franklin was named deputy postmaster of the city, but service was slow and not always reliable. During the remainder of the century, significant improvements in delivery were made, but some townspeople devised ingenious ways of transmitting information even faster than the mails. Philadelphia stock exchange brokers, for instance, communicated with agents in New York by flashing coded signals with mirrors and lights from a series of high points across New Jersey, thereby receiving stock prices on the same day they were transacted. By 1846, the first telegraph service in the state linked Harrisburg and Lancaster.
In 2001, 97.0% of Pennsylvania's households had telephones. Pittsburgh's KDKA became the world's first commercial radio station in 1920. By 2003, it was one of 52 major AM and 144 major FM radio stations. In addition, there were 34 major television stations. WQED in Pittsburgh pioneered communitysponsored educational television when it began broadcasting in 1954. In 2000, the Philadelphia area had 2,670,710 households, 79% with cable; the Pittsburgh area had a 79% penetration rate in 1,135,290 households; and the Harrisburg-Lancaster-Lebanon-York area had 599,930 households, 78% with cable.
A total of 217,724 Internet domain names were registered in the state by the year 2000.