Douglas Harper's Etymology Dictionary
in figurative sense of "first-rate," 1837, in Dickens; from Lloyd's of London designation for ships in first-class condition (with the letter referring to the condition of the ship and the number to that of the stores).
Alastair Charles Ralphs (born May 22, 1977) is a Canadian professional wrestler and former bodybuilder, better known by his ring name, A-1 (alternatively spelled A1 or A-One). He is best known for his appearances with Total Nonstop Action Wrestling (TNA) from 2004 to 2007 as part of Team Canada.
A-1 was the designation for a code used by the United States Navy during World War I that replaced the Secret Code of 1887, SIGCODE and another system designed for radio communication. The cryptographic system was developed by Lt. W.W. Smith in the Office of Naval Operations by randomly associating key words with 5 letter patterns.