Iota and Jot

Iota and Jot are two extremely minimalist formal languages designed by the linguistics professor Chris Barker in 2001, built to be even simpler than the lambda calculus and the SKI combinator calculus. Their names come from the smallest letters of the Greek and Hebrew alphabets. Both use only two symbols and two operations, yet both are Turing complete, which is why they are counted among the Turing tarpits, the esoteric programming languages that aim to be as small as possible. Iota is a prefix notation for trees built from one universal combinator and function application. Jot is the regular language of all strings of zeros and ones, with meaning given by translation into SKI expressions, which makes it a natural numbering of all algorithms. Zot, a 2002 successor to Iota, adds input and output through continuation passing style.