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 abbreviations provided by the prosigns for Morse code, the International Q code, Z code, RST code, the telegraph era Phillips Code and many well known Morse code abbreviations as discussed in this Wikipedia article. Together all of these traditional conventions serve as a somewhat cryptic but commonly understood language (Lingua Franca) within the worldwide community of amateur radio Morse code operators. These codes and protocols efficiently encode many well known statements and questions from many languages into short simple character groups which may be sent manually very quickly. The international Q code for instance encodes literally hundreds of full normal language