In order to prevent ambiguities in the allocation of an alphanumeric character, the alphanumeric character to be allocated is selected from a dynamically modifiable set of characters.

Each pattern represents an alphanumeric character for recognition by a visually impaired individual.

Preferably, the pattern comprises an alphanumerical character, a logo and/or an arrow.

The name must begin with an alphanumeric character.

Frame names must start with an alphanumeric character.

The name must start with an alphanumeric character.

Dataset names must begin with an alphanumeric character.

Optionally, the one-time code in an alphanumeric form placed by the computer in the CID fields contains at least on masking alphanumeric character.

The value of the NAME attribute must begin with an alphanumeric character.

with an alphabetic character and end with an alphanumeric character.

case-sensitive and must start with an alphanumeric character.

An address must begin and end with an alphanumeric character.

They must begin with an alphabetic character and end with an alphanumeric character.

Dataset names must begin with an alphanumeric character.

The a character permits an alphanumeric character in this position, but doesn't require it.