> Naturally, symbols like "←" or "⇐" weren't available, but even the characters ":" and "<" were not on the 026 keypunch keyboard and so ":=" or "<-" were much

> Naturally, symbols like "←" or "⇐" weren't available, but even the characters ":" and "<" were not on the 026 keypunch keyboard and so ":=" or "<-" were much harder to punch on a card. This explains why early ALGOL implementations (e.g. Burroughs, the only dwarf who went all in on the language) and dialects (ALGO, JOVIAL, MAD, NELIAC) actually used ‘=’ for assignment. This was perfectly legal according to the language definition, which distinguished between the ‘reference language’, which used ‘:=’, and its ‘hardware representation’, which could be anything. (Naturally there was no portability.)