What can JavaScript do?

JavaScript gives HTML designers a programming tool

HTML authors are normally not programmers, but JavaScript is a scripting language with a very simple syntax! Almost anyone can put small "snippets" of code into their HTML pages.

JavaScript can put dynamic text into an HTML page

A JavaScript statement like this: document.write("<h1>" + name + "</h1>") can write a variable text into an HTML page.

JavaScript can react to events

A JavaScript can be set to execute when something happens, like when a page has finished loading or when a user clicks on an HTML element.

JavaScript can read and write HTML elements

A JavaScript can read and change the content of an HTML element.

JavaScript can be used to validate data

A JavaScript can be used to validate form data before it is submitted to a server, this will save the server from extra processing.

JavaScript can be used to detect the visitor's browser

A JavaScript can be used to detect the visitor's browser, and - depending on the browser - load another page specifically designed for that browser.

JavaScript can be used to create cookies

A JavaScript can be used to store and retrieve information on the visitor's computer.