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JavaScript
is the most popular scripting language on the internet, and works in
all major browsers, such as Internet Explorer, Firefox, Chrome, Opera,
and Safari.
What You Should Already Know
Before you continue you should have a basic understanding of the following:
If you want to study these subjects first, find the tutorials on our Home page.
What is JavaScript?
- JavaScript was designed to add interactivity to HTML pages
- JavaScript is a scripting language
- A scripting language is a lightweight programming language
- JavaScript is usually embedded directly into HTML pages
- JavaScript is an interpreted language (means that scripts execute without preliminary compilation)
- Everyone can use JavaScript without purchasing a license
Are Java and JavaScript the same?
NO!
Java and JavaScript are two completely different languages in both concept and design!
Java (developed by Sun Microsystems) is a powerful and much more
complex programming language - in the same category as C and C++.
What can a 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 saves 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
The Real Name is ECMAScript
JavaScript's official name is ECMAScript.
ECMAScript is developed and maintained by the ECMA organization.
ECMA-262 is the official JavaScript standard.
The language was invented by Brendan Eich at Netscape (with
Navigator 2.0), and has appeared in all Netscape and Microsoft browsers
since 1996.
The development of ECMA-262 started in 1996, and the first edition of was adopted by the ECMA General Assembly in June 1997.
The standard was approved as an international ISO (ISO/IEC 16262) standard in 1998.
The development of the standard is still in progress.
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