Subsets of alphanumeric used in human interfaces Alphanumeric

when string of mixed alphabets , numerals presented human interpretation, ambiguities arise. obvious similarity of letters i, o , q numbers 1 , 0. therefore, depending on application, various subsets of alphanumeric adopted avoid misinterpretation humans.

in passenger aircraft, aircraft seat maps , seats designated row number followed column letter. wide bodied jets, seats can 10 across, labeled abc-defg-hjk. letter skipped avoid mistaking row number 1.

in vehicle identification number used motor vehicle manufacturers, letters i, o , q omitted similarity 1 or 0.

tiny embossed letters used label pins on v.35/m34 electrical connector. letters i, o, q, s , z dropped ease eye strain 1, 0, 5, 3,and 2. subset named dec alphabet after company first used it.

for alphanumerics handwritten, in addition , o, v avoided because looks u in cursive, , z similarity 2.