The Tiresias family of fonts has been designed for use in multiple environments
to help improve legibility, especially for individuals with visual impairment.
It includes specialized fonts for information labels, control labels (for key
tops), large print publications, computer systems, television subtitling, and
signs.
The Signfont family is specialized for preparing signs for the visually
impaired, using large characters. The only difference between the Signfont and
the Signfont Z families is whether the zero is crossed out or not. In the
Signfont family, the zero is _not_ crossed out, which may lead to some
confusion.