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
Braille pattern dots-356 Braille pattern dots-356 The Braille pattern dots-356 ( ) is a 6-dot braille cell with the middle right and both bottom dots raised, or an 8-dot braille cell with the upper-middle right and both lower-middle dots raised. It is represented by the Unicode code point U+2834, and in Braille ASCII with the number 0. In unified international braille, the braille pattern dots-356 is used to represent various punctuation, often coupled with Braille pattern dots-236 as an closing mark. † Abolished in Unified English Braille Related to Braille pattern dots-356 are Braille patterns 3567, 3568, and 35678, which are used in