Introduction JavaScript is arguably the most misunderstood programming language in usetoday. 1 The natural supposition that it has something to do with Java turns out to be quite mistaken; in fact, though both languages inherit the syntax ofC and are interpreted, further similarities are not easy to find. In JavaScript,functions are first-class objects. Functions can return functions built on thefly or accept other functions as arguments. Almost any kind of property canbe added to any object at any time, and object properties can be inspectedat run-time. JavaScript is weakly-typed in the strongest sense of the term:virtually every type conversion is implicit. JavaScript is lexically scoped,which makes coding in JavaScript feel more like hacking Lisp than writingJava classes. As a matter of fact, JavaScript and Lisp are so closely relatedthat a compiler from Lisp to JavaScript can be implemented in less than100 lines of code. 2 One need not be a devotee of the Lambda Calculus to find such a possibility fascinating.