JavaScript Basics of front-end development

Main content:

1. JavaScript Introduction

2. How JavaScript is introduced

3. JavaScript variables and Naming conventions

4. Five basic types of data

5. Operators

6. String processing

7. Data type Conversion

First, JavaScript introduction

1. What is JavaScript?

     JavaScript is a descriptive language for the Web front-end, and is a well-secured scripting language based on object and event-driven (driven).  it runs on the client side thereby easing the burden on the server.

Has the following characteristics:

(1) JavaScript is used primarily to add interactive behavior to HTML pages. (2) JavaScript is a scripting language, and the syntax is similar to the language of the C language family language, which is a weak language type. (3) JavaScript is typically used to write client-side scripting, except for node. js. (4) JavaScript is an interpreted language, which does not need to be compiled in addition to the side-execution side interpretation.

2. What is JavaScript used for?

The purpose of JavaScript is to resolve page interactions and data interactions, with the ultimate goal of enriching client-side effects and effectively delivering data. Specifically:    (1) achieve page interaction, enhance the user experience to achieve page effects. That is, JS operates the DOM structure or operation style of the HTML.    (2) The client form verification is the timely and effective verification of the user submitted information before the data is delivered to the server, alleviating the server pressure. That is, data interaction.

3. What is the relationship between JavaScript and ECMAScript?

Difference:     ECMAScript is the Web standard for scripting programming languages.     JavaScript is a lightweight, interpreted scripting language. Contact:     Ecmascripts is the European Computer Manufacturing Association, JavaScript and Microsoft Inc., a Netscape invented by the American Netscape Communications company, then developed the ECMAScript standard in imitation of the JavaScript scripting language.    

4. What are the parts of JavaScript?

There are three main parts:    ECMAScript, DOM, BOM, respectively.    Dom is when a page is loaded, the browser creates a Document object model of the page.    BOMs refer to the Browser object model (Browser object models), and there is no formal standard.

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JavaScript Basics of front-end development