What parts does javascript consist of?

Javascript consists of three parts, namely: 1. The ECMAScript part refers to the core, which is an internationally recognized standard scripting language specification; 2. The DOM part refers to the Document Object Model; 3. BOM section, refers to the browser object model.

The operating environment of this article: Windows 7 system, JavaScript version 1.8.5, DELL G3 computer.

What are the parts of javascript?

Although JavaScript and ECMAScript are often used to express the same meaning, JavaScript has much more meaning than what is specified in ECMA-262. A complete JavaScript implementation should be composed of three parts:

1. Core (ECMAScript)

2. Document Object Model (DOM)

3. Browser Object Model (BOM)

Core (ECMAScript)

ECMAScript defined by ECMA-262 is an internationally recognized standard scripting language specification that has no connection with web browsers Dependencies. The ECMA-262 standard mainly stipulates that this language consists of the following components:

1. Grammar

2. Variables and data types

3. Keywords and reserved words

4.Operator

5.Control statement

6.Object

In 2009, ECMAScript version 5.0 was officially released. For a long time, JavaScript was used in accordance with the 5.0 standard. In 2015, ECMAScript 6 was released as an official version, officially called ECMAScript 2015. ECMAScript defines all properties, methods and objects of the scripting language. Therefore, you must follow the ECMAScript standard when coding web client scripts.

Document Object Model (DOM)

DOM (Document Object Model) is the application programming interface (API) for HTML and XML. DOM will plan the entire page into a document composed of node hierarchies. Each component in an HTML or XML page is a node of some type, and these nodes contain different types of data.

Browser Object Model (BOM)

IE 3.0 and Netscape Navigator 3.0 provide a feature - BOM (Browser Object Model), which can access and operate. Using the BOM, developers can move windows, change text in the status bar, and perform other operations not directly related to the content of the page.

Recommended study: "javascript basic tutorial"

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