A Verb is the primary response, being a word containing only the alphanumeric
characters a-z, A-Z or 0-9, together with the underscore ``_" and dollar ``$"
characters.
Verbs may be defined as having up to 32 characters, where only the first 8
are treated as significant by default. This default may be overridden by
an Application Program however.
Verbs are associated with Groups, the default Group being assumed unless
explicitly overridden. Verbs within the same Group must be unique, but each
Group may contain Verbs that conflict with Verbs from other Groups. Only
a single Group of verbs may be ``active" at any one time. Groups are identified
by a number in the range 0 to 4095, where Group 0 is assumed by default.