What does the web use for information transfer?

web uses HTTP protocol for information transmission.

## HTTP is a simple request-response protocol that usually runs on top of TCP. It specifies what kind of messages the client may send to the server and what kind of response it gets. (Recommended learning: PHP video tutorial)

The headers of request and response messages are given in ASCII code form; while the message content has a MIME-like format. This simple model was instrumental in the early success of the Web because it made development and deployment so straightforward.

Introduction

The World Wide Web WWW (world wide web) originated from CERN, the quantum physics laboratory in Geneva, Europe. It is the emergence of WWW technology that enables the Internet to surpass Imagination moves at a rapid pace.

This TCP/IP-based technology has quickly become the largest information system on the Internet that has been developed for decades in just ten years. Its success is attributed to its simplicity and practicality. . Behind WWW, there are a series of protocols and standards that support it in accomplishing such impressive work. This is the

Web protocol family, which includes the HTTP Hypertext Transfer Protocol.

In 1990, HTTP became the supporting protocol of the WWW. It was proposed by its founder Tim Bemers-Lee, the father of WWW, and then the WWW Consortium was established and organized the IETE (Internet Engineering Task Force) group to further improve and release the HTTP protocol. [2]

HTTP is an application layer protocol. Like other application layer protocols, it is a protocol for implementing a certain type of specific application, and its functions are implemented by an application running in user space. HTTP is a protocol specification, which is recorded in the document.

is the implementation program of HTTP that actually communicates through the HTTP protocol.

The HTTP protocol communicates based on the C/S architecture. The server-side implementation programs of the HTTP protocol include httpd, nginx, etc. The client-side implementation programs are mainly web browsers, such as Firefox and Internet Explorer. , Google chrome, Safari, Opera, etc. In addition, the client's command line tools include elink, crul, etc.

Web service is based on TCP, so in order to respond to client requests at any time, the Web server needs to listen on port 80/TCP. The client browser and the web server can communicate through the HTTP protocol.

At the beginning of HTTP's birth, it was mainly used for content acquisition on the WEB side. At that time, the content was not as rich as it is now, the layout was not as exquisite, and there were almost no user interaction scenarios.

For this simple scenario of obtaining web content, HTTP performs pretty well. But with the development of the Internet and the birth of WEB2.0, more content began to be displayed (more picture files), layout became more exquisite (more CSS), and more complex interactions were introduced (more jS). The total amount of data loaded and the number of requests when a user opens the homepage of a website are also increasing.

For more PHP-related technical articles, please visit the

PHP Graphic Tutorial column to learn!

The above is the detailed content of What does the web use for information transfer?. For more information, please follow other related articles on the PHP Chinese website!