Overview of JavaScript learning experience _ basic knowledge

This article mainly introduces some basic things of javascript, including the introduction of javascript and the introduction of the & lt; script & gt; elements. It also gives you a better understanding of javascript through examples, very good. I recommend it to you. 1. JavaScript is a scripting language designed for interaction with webpages.

ECMAScript (CORE) DOM (Document Object Model) BOM (Browser Object Model)

1.1 ECMAScript

ECMA-262-defined ECMAScrip has no dependency with Web browsers, ECMA-262 defines only the basis of this language, providing core language functionality

ECMAScript is a scripting language standardized through the ECMA-262, The ECMA-262 specifies the language: syntax, type, statement, keywords, reserved words, operators, objects

1.2 DOM (Document Object Modle)
DOM is an XML but extended Application Programming Interface (API) for HTML. It provides methods and interfaces for accessing and operating webpage content.

DOM maps the entire page into a multi-layer node structure. Each component of pages such as HTML and XML is a certain type of node, and these nodes contain different types of data.

1.3 BOM (Bower Object Modle)
The BOM only processes browser windows and frameworks and provides methods and interfaces for interacting with browsers.

Ii. script elements
2.1 reference javascript files
External Reference javascript file:

The Code is as follows: