Telegraphy:

Telegraphy (from the Greek words tele (τηλε) = far and graphein (γραφειν) = write) is the long-distance transmission of written messages without physical transport of letters. Radiotelegraphy or wireless telegraphy transmits messages using radio. Telegraphy includes recent forms of data transmission such as fax, email, and computer networks in general.[citation needed]
A telegraph is a machine for transmitting and receiving messages over long distances, i.e., for telegraphy. The word telegraph alone now generally refers to an electrical telegraph. Wireless telegraphy is also known as CW, for continuous wave (a carrier modulated by on-off keying), as opposed to the earlier radio technique using a spark gap.[citation needed]
A telegraph message sent by a telegraph operator (or telegrapher) using Morse code was known as a telegram or cablegram, often shortened to a cable or a wire message. Later, a telegram sent by the Telex network, a switched network of teleprinters similar to the telephone network, was known as a telex message.
Before long distance telephone services were readily available or affordable, telegram services were very popular. Telegrams were often used to confirm business dealings and, unlike email, telegrams were commonly used to create binding legal documents for business dealings.[citation needed]