Logo interpreter, written in Java
Logo is a programming language developed in the 1970's by Seymour Papert. It is an excellent language to begin learning with, as it teaches the basics of things like loops, tests, procedures, etc. The user moves an object called a "turtle" around the screen using commands as simple as forward, back, right, and so on. As it moves, the turtle leaves a trail behind it, and so it is therefore possible to create drawings. Operations on lists and words are also possible.