Abstract: A character generator uses a first memory having a permanent resident area and an overlay area. A second memory stores patterns of all characters. The permanent resident area stores character patterns having the highest frequency of use. The overlay area is not permanent and stores a subset of character patterns known to have high frequency use, but of lesser frequency than in the permanent area. A directory is provided for accessing character patterns in the overlay area. Characters are accessed using character code points. Each character code point represented in the directory has a usage count field and an address pointer field for enabling the character to be chained in a logical sequence with the other characters in accordance with their respective frequencies of use. The directory is searched serially and the search time will be shorter for the characters having highest frequency of use. The characters are accessed in the directory by their code points.