What are the common framework structures of IT training sharing web front-end development?

With the continuous development of the Internet, more and more programmers begin to learn and master the relevant technical knowledge about web front-end development. Today, let's take a look at the common frameworks that web front-end development needs to understand and master.

First, socket communication

When it comes to the web, we can't do without tcp and http (https protocol is complicated, which is beyond the scope of this chapter for the time being). Http protocol is behind, so what is tcp protocol? Cp protocol is the transport layer of the network, which is used to transmit data. Tcp protocol is relatively safe and reliable. The main connection process is as follows. The client sends a SYN request including a random number seq. Assuming that the value of this random number is equal to I, the server will send an ack request, add 1 to this random number and send it to the client at the same time. After receiving the ack from the server, the client will also send ACK to the server (this is only a general description of tcp three-way handshake, and you can go to the tcp/ip protocol volume if you want to know more).

Http is an application layer protocol, and its transport layer is tcp protocol. It can be said that sock communication is the underlying communication of web services. Without sockets, there would be no http protocol, let alone web services.

Second, the structure.

There are mainly c/s architecture and b/s architecture. c/s is mainly composed of applications and remote servers that need to be installed on the client. Its advantage is less communication between the two parties, because most of the information is stored locally, but its disadvantage is that the maintenance and upgrade of the client are troublesome, and it is generally suitable for large-scale systems.

B/s architecture consists of browser and server. Its advantage is that it is convenient and you can surf the Internet at any time. Its disadvantage is that the communication volume is large and it is not particularly stable compared with c/s;

C/s architecture

B/s architecture

Third, the working principle of web applications

Web applications can be roughly divided into two types: dynamic websites and static websites. A static website is a static page written in HTML. Dynamic websites dynamically generate different pages according to different requests of users and send them to clients. Usually written in HTML and dynamic scripting languages (ASP, PHP, JSP). The following pictures are from the Internet.

When developing Web applications, it is usually necessary to apply both client-side and server-side technologies. Among them, IT training thinks that the technology of client application is mainly used to show information content, and the technology of server application is mainly used to deal with business logic and interact with database.

Fourthly, HTTP protocol.

In order to make the web service of the Internet flourish and make the client and server comply with some protocols, http appeared. Http protocol can be said to be one of the great protocols, including 1.0, 1. 1 and 2.0.