A predecesor of the modern computer, the Jacquard Loom .

jacquard loom

A simple computer program that recreates the conditions for its continuing recreation.

var l = document.getElementsByTagName("pre").length - 1;
var main = function(){  
var program = document.getElementById("program");
var pre = document.createElement( "pre");
var text = document.createTextNode( 'var l = document.getElementsByTagName("pre").length - 1; var main = ' + main + "; main();");
pre.appendChild(text);
program.appendChild(pre);
pre.onclick = function(){ 
this.style.color = '#B48D4A';
eval(document.getElementsByTagName( "pre")[l].innerHTML);
};}; main();