The MinChar(s) command computes the least character present in the string s. The MaxChar(s) command computes the greatest character present in the string s. Characters are ordered by their byte values (1-255).

All of the StringTools package commands treat strings as (null-terminated) sequences of $8$-bit (ASCII) characters.  Thus, there is no support for multibyte character encodings, such as unicode encodings.

$\mathrm{with}\left(\mathrm{StringTools}\right)\:$

$\mathrm{MinChar}\left(''badc''\right)$

$''a''$

$\mathrm{MaxChar}\left(''badc''\right)$

$''d''$