JavaScript Advanced Program Design reading notes-(1) Introduction to JavaScript

Overview

JavaScript is a literal-translation scripting language, a dynamic type, a weak type, a prototype-based language, and a built-in support type. Its interpreter, known as the JavaScript engine, is widely used as a scripting language for the client, and is used in HTML (an application under the standard Universal Markup Language) to add dynamic functionality to an HTML Web page. However, JavaScript can now also be used for Web servers such as node. js.

Differentiate between Java and JavaScript

JavaScript was first designed and implemented by Netscape Brendan Eich in 1995. As Netscape and Sun co-operate, the Netscape high-level wants it to look like Java, so it's named JavaScript. So, JavaScript has nothing to do with Java itself.

JavaScript components

JavaScript has the following 3 major components:

1. Core (ECMAScript), defined by ECMA-262, provides core language functions;
2. Document Object Model (DOM), which provides methods and interfaces for accessing and manipulating Web page content;
3. A Browser object model (BOM) that provides content and interfaces that interact with the browser.

ECMAScript compatibility

Here are the different versions of the Ecma-script Compatibility List for each major mainstream browser:

DOM Standard Support

Here is a table of the current mainstream browser support for DOM standards:

JavaScript Advanced Program Design reading notes-(1) Introduction to JavaScript