Web Basic Concepts

1. Basic Concepts

1.1, Overview

1) web development:

• web, the meaning of web pages

• static web

  • html, css
  • The data that is available to all will never change

• Dynamic web

  • Changes happen, and everyone sees different information at different times and places!
  • Taobao, almost all websites
  • Technology stack: Servlet/JSP ,ASP , PHP

  In java, the technology of dynamic web resource development is collectively referred to as JavaWeb

1.2, web application

web application: a program that provides browser access:

• URL
• This unified web resource will be placed in the same folder, web application ->Tomcat:server
• A web application consists of multiple parts:
  • html, css, js
  • jsp, servlet
  • java program
  • jar package
  • Configuration file

After the web application is written, if you want to provide access to the outside world, you need a server for unified management

1.3, static web

Client-----Request----->Server

Server-----Corresponding------>Client

• *html These are the suffixes of web pages. If these things always exist on the server, we can read them directly.
• Disadvantages of static web
  • Web pages cannot be dynamically updated, all users see the same page
  • It cannot interact with the database (data cannot be persisted and users cannot interact)

1.4, dynamic web

The page will be displayed dynamically

Disadvantages:

• There is an error in the dynamic web resource added to the server, we need to rewrite our background program and republish
  • Downtime for maintenance

Advantages:

• Web pages can be dynamically updated, and all users will not see the same page
• Can interact with the database, data persistence

2, web server

2.1, technical explanation

ASP:

• Microsoft: ASP is the first popular in China;
• Embedding VB script in HTML, ASP+COM;
• In ASP development, basically a page has thousands of lines of business code, and the page is disordered
• High maintenance costs
• C#

php

• PHP development is fast, powerful, cross-platform, and the code is very simple
• Unable to handle large traffic; limited

JSP/Servlet:

• The B/S architecture promoted by sun company
• Based on java language
• Can bear the impact of the three high problems (high concurrency, high availability and high performance)

2.2, web server

The server is a passive operation, used to process some requests from users and give users some corresponding responses

Tomcat, IIS

IIS: Microsoft; comes with Windows