Morse code was later made the standard by the International Telecommunication Union (ITU). Morse's original code specification, largely limited to use in the United States and Canada, became known as American Morse code or "railroad code". American Morse code is now seldom used except in historical re-enactments. In aviation, pilots use radio navigation aids. To ensure that the stations the pilots are using are serviceable, the stations transmit a set of identification letters (usually a two-to-five-letter version of the station name) in Morse code. Station identification letters are shown on air navigation charts. For example, the VOR-DME based at Vilo Acuña Airport
Morse code for non-Latin alphabets not have a Morse equivalent, with Е used instead. Hebrew letters are mostly represented using the Morse representation of a similar-sounding Latin letter (e.g. "Bet" ב≡B); however the representation for several letters are from a Latin letter with a similar shape (e.g. "Tet" ט ≡U, while "Tav" ת≡T). See also The following telegraph code table is adapted from one given by Ashok Kelkar, where the Latin letters are encoded as per the International Morse code standard. Some variations on this code exist, and there have been some attempts to introduce other telegraph codes to add efficiency and make it suitable