AMOS uses the following rules for names:
Can't start with a digit.
'0' thru '9', 'A' thru 'Z' and 'a' thru 'z', '_' are all legal after that but note all upper case letters are stored as lower case (AMOS displays as upper case - but that can be changed in the editor's config file).
Then comes the interesting bit - any ASCII character from Chr$($81) thru Chr$($FF) is also legal. Presumably to allow international characters to be used.
As this range also includes a few other symbols, the results can be quite hilarious. Try checking out the characters you can type with the [Alt] key held down and you'll see what I mean.
Personal favourite is to be able to type "1/4=1" where the "1/4" is the symbol character. One can make almost unreadable code this way but I wouldn't recommend it!
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