Front-End Basics: JavaScript Introduction

JavaScript introduction

Introduction to JavaScript

• 1. In 1995, Brendan Eich, a Netscape company, was first designed to achieve layer two on the Netscape Navigator browser, because Netscape worked with Sun and Netscape management wanted it to look like Java and therefore named JavaScript. But in fact its grammatical style is closer to self and scheme;
• 2. In order to gain a technical advantage, Microsoft introduced the Jscript,cenvi exit Scriptease, and JavaScript can also be run on the browser, in order to uniform specifications, because JavaScript is compatible with the ECMA standard, so also known as ECMAScript;

JavaScript Basic Features
JavaScript is a network scripting language, has been widely used in Web application development, often used to add a variety of dynamic features for Web pages, to provide users with more smooth and beautiful browsing effect, JavaScript scripts are typically embedded in HTML to implement their own functionality.

• 1. is an explanatory scripting language (code is not precompiled);
• 2. It is mainly used to add interactive behavior to HTML (an application under standard Universal Markup Language) page;
• 3. The HTML page can be embedded directly, but a separate JS file is advantageous to the separation of structure and behavior;
• 4. Cross-platform features, under the support of most browsers, can be run on a variety of platforms (such as: Windows, Linux, Mac, Android, iOS, etc.);

The JavaScript scripting language, like other languages, has its own basic data type, expression and arithmetic operators, and the basic process framework of the program. JavaScript provides four basic data types and two special data types to handle data and text. The variable provides the place where the information is stored, the expression can complete the more complex processing.

JavaScript components

• ECMAScript: Describes the grammar and basic objects of the language;
• Document Object Model (DOM): Describes methods and interfaces for handling Web page content;
• Browser object Model (BOM): Describes methods and interfaces for interacting with the browser

To put it simply, ECMAScript describes the following:

• Syntax
• Type
• Statement
• keywords;
• Reserved words;
• operator
• Object, based on the object-oriented language;

JavaScript basics

Front-End Basics: JavaScript Introduction