A char-table is a one-dimensional array of elements of any type, indexed by character codes. Char-tables have certain extra features to make them more useful for many jobs that involve assigning information to character codes—for example, a char-table can have a parent to inherit from, a default value, and a small number of extra slots to use for special purposes. A char-table can also specify a single value for a whole character set.
The printed representation of a char-table is like a vector except that there is an extra ‘#^’ at the beginning.1
See Char-Tables, for special functions to operate on char-tables. Uses of char-tables include:
 You may also encounter ‘#^^’, used for “sub-char-tables”.