The Howdy Glossary

The Internal Translator (IT) — also known as ITL — is a programming language used on the IBM 1401 Computer and its successors. Developed in the late 1950s, it's designed to compile programs into machine code directly executed by the system without needing additional assembly or compiling steps. Part of its innovation comes from being one of the first examples of self-hosting compilers: an IT compiler runs on an IBM 1401, and it can compile subsequent versions of itself. This made software development more efficient for early computer users who had limited resources for development and testing.