a dynamic, weakly typed, prototype-based language with first-class functions.
//Compilation and execution happen together. var propMap = { val: "value", html: "innerHTML" }; for(var fnName in propMap){ $.prototype[fnName] = (function(prop){ return function(){ return this[prop]; } })(propMap[fnName]); }//Type associated with value, not variable. var a = 1; a = "one"; a = [1]; a = {one: 1};//Treat like any object var square = function(x){ return x*x }, //create mult = function(f1, f2){ // Return return function(n){ return f1(n)*f2(n); } }, bigF = mult(square, square), // ARG value = bigF(2); // 16
JavaScript (JS) is a lightweight, interpreted or JIT compiled programming language with first-class functions. Most well-known as the scripting language for Web pages, many non-browser environments also use it, such as node.js and Apache CouchDB. JS is a prototype-based, multi-paradigm, dynamic scripting language, supporting object-oriented, imperative, and declarative (e.g. functional programming) styles.