`mkid' is a simple, fast, high-capacity, language-independent identifier database tool. Actually, the term `identifier' is too limiting--`mkid' stores tokens, be they program identifiers of any form, literal numbers, or words of human-readable text. Database queries can be issued from the command-line, or from within emacs, serving as an augmented tags facility. `mkid' was originally written by Greg McGary and posted to comp.sources.unix in September 1987. It was then maintained and enhanced by a loose knit group of programmers on the Internet led by Tom Horsley . Tom released `mkid2' on comp.sources.unix in March, 1991. Since then, Greg McGary has resumed maintenance and is releasing an improved version 3 under GPL.