JavaScript is a dynamically typed imperative programming language with functional features. JavaScript is the main language for programming web pages; however it's use as a general purpose programming language is growing.

JavaScript is generally interpreted.

function doors (n) {
	// Create an array with 100 objects
	var is_open = [];
	// Initialize the array values to false
	for (var i = 0; i < n; i++) {
		is_open[i] = false;
	// Process the doors
	for (var step = 0; step < n; step += 1) {
		for (var idx = step; idx < n; idx += step+1) {
			is_open[idx] = !is_open[idx];

	// Print the results
	for (i = 0; i < n; i++) {
		if (is_open[i]) {
			console.log("Door #" + (i+1) + " is open.");
		} else {
			console.log("Door #" + (i+1) + " is closed.");


Why would I learn this language?

JavaScript is the language of the internet. To create an interactive website, JavaScript is the best choice. The web browser is a very capable application development platform and is available for the majority of platforms.

JavaScript has excellent debugging tools and due to the nature of its execution environment, provides a rich set of elements (such as images, audio and text) for displaying results.

JavaScript is a semantically simple language with first-class functions. This makes it very easy to use advanced functional concepts.

Starting Points

Eloquent JavaScript
An interactive online tutorial for the beginner programmer.
Learning Advanced Javascript
A set of tutorials covering advanced computer programming topics in JavaScript.
A fantastic tool for developing and debugging JavaScript in FireFox.
Mozilla Developer Network
A great set of resources and documentation for programming JavaScript in the web browser.
A fantastic toolbox for writing simple cross-browser JavaScript code. Includes support for many advanced features.
Best Resources to learn JavaScript
A list of resources and books for learning JavaScript.

Further Reading