A little language that compiles into JavaScript.
The web was not built for the interactivity we have come to expect of it. Web pages were originally designed to contain static text and images. Hyperlinks were a way to travel between these static pages but, that was the extent of a page's interactivity.
Java and JavaScript emerged as competitors (Java is to JavaScript as Car is to Carpet) in web browsers promising to add a new level of dynamic content and interactivity.