[JavaScript] Introduction to Javascript

In millions of pages, JavaScript is used to improve design, validate forms, detect browsers, create cookies, and so on.

Javascript is the most popular scripting language on the Internet and can run in all major browsers, such as Internet Explorer, Mozilla, Firefox, Netscape, and opera.

Basic knowledge you should possess:

Before continuing to learn, you should have a basic understanding of the following:

• Html
• XHTML

If you want to learn this content first, visit the relevant tutorials on the homepage.

What is JavaScript?

• Javascript is designed to add interactions to HTML pages.
• Javascript is a scripting language (scripting language is a lightweight programming language ).
• JavaScript consists of several lines of executable computer code.
• Javascript is usually directly embedded into HTML pages.
• Javascript is an interpreted language (that is, code execution is not precompiled ).
• All users do not need to buy a license to use JavaScript.

Is java the same as JavaScript?

Different!

Java and JavaScript are two completely different languages in terms of concept and design.

Java (developed by Sun Microsystems) is powerful and more complex programming languages, just like C and C ++ at the same level.

What can JavaScript do?

Javascript provides HTML designers with a programming tool.

HTML creators are often not programmers, but Javascript is a scripting language with extremely simple syntax! Almost everyone has the ability to put short code snippets into their HTML pages.

Javascript can add dynamic text to HTML pages.

A JavaScript declaration similar to this can put a variable piece of text on an HTML page: Document. Write ("

Javascript can respond to events

You can set JavaScript to be executed only when an event occurs. For example, when a page is loaded or an HTML element is clicked.

Javascript can read and write HTML elements.

Javascript can read and change the content of HTML elements.

Javascript can be used to verify data

Javascript can be used to verify the data before it is submitted to the server.

Javascript can be used to detect visitors' browsers

Javascript can be used to detect the visitor's browser and load the corresponding page for the browser based on the detected browser.

Javascript can be used to create cookies.

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

The actual name is ecmascript.

The official name of JavaScript is "ecmascript ". This standard is developed and maintained by ECMA.

ECMA-262 is the formal JavaScript standard. This standard is based on JavaScript (Netscape) and JScript (Microsoft ).

The Brendan eich of Netscape (navigator 2.0) invented the language and has appeared in all Netscape and Microsoft browsers since 1996.

The development of ECMA-262 began in 1996, and in July 1997, The ECMA Member Conference adopted its first version.

In 1998, the standard became an international ISO standard (ISO/IEC 16262 ).

This standard is still under development.