JavaScript Learning Notes (a) Introduction to JavaScript

This series of blogs focuses on notes in the process of learning JavaScript Advanced Programming (third edition).

A complete web-side JavaScript implementation should have three main components: The language core ECMAScript, the Document Object Model DOM, and the browser object model BOM (Browser objects Model).

ECMAScript (hereinafter referred to as ES) is not an egg-dependent relationship with a Web browser, it is just the underlying definition of the language, and web browsers are just one of the hosting environments implemented by ES. ES specifies the following components of the language: syntax, type, statements, keywords, reserved words, operators, and objects.

Dom is an application programming interface (API) for XML but is extended for HTML, and the DOM maps the entire page into a tree-like node structure, and provides an API for the developer to easily perform the redaction operation on the DOM node. Note that DOM is not intended for JavaScript, and many other languages implement DOM as well.

The BOM is primarily used to manipulate browser-related properties and methods. The BOM is part of the JavaScript implementation, but there are no relevant standards at this time, and many browsers have their own implementations. HTML5 is expected to enable the BOM to become more and more compatible with the direction of development. (HTML5 Dafa is good!) ）

JavaScript Learning Notes (a) Introduction to JavaScript