On some places, metadata values are interpreted as a truth value.

Every character sequence that begins with a “0”, “F”, “N”, “f”, or a “n” is interpreted as the boolean “false” value.
All other values are interpreted as the boolean “true” value.

However, there is no full support for a boolean type.
Such values are interpreted as a [string value](00001006033500), e.g. with respect to comparing and sorting.