Description of Mini Javascript Editor :
MJE is an online JavaScript testing tool that allows you to enter and execute JavaScript code on the fly. You can send output to the JavaScript Output field by calling the built-in out() method from within the JavaScript Input field. The out() method accepts one parameter, and sends that value to the JavaScript Output field. For example, the code out("foo"), in the JavaScript Input field will cause the text foo to be printed to the JavaScript Output field