With regard to the network HTTP protocol, the HTTP protocol refers to:

This involves the knowledge of cookis, check out this:

Cookies were developed by Netscape as a way to persistently store state and other information, and most browsers currently support the cookie protocol. A cookie is a text file stored in your browser directory that records your visit to a particular site and can only be read back by the site that created the cookie, consisting of about 255 characters and taking up only 4 KB of hard disk space. When the user is browsing a site, it is stored in the RAM of the user's RAM and on the user's hard drive when the browser is exited.

Most of the information stored in cookies is ordinary, such as when you visit a site, this file records every keystroke and the address of the visited site. However, many web sites use cookies to store personal data, such as registration passwords, usernames, credit card numbers, etc.

Because cookies are stored in the form of standard text files and therefore do not pass on any viruses, the cookies themselves are safe and secure in the sense of the average user. Since a cookie is a unique identifier that a web server places on your machine and can retrieve your profile, web site administrators can use cookies to create detailed profiles about users and their browsing characteristics. When a user logs in to a website, information about clicks made on any web page that has cookies set is added to the file.

For the time being, this information in the file is mainly used for the design and maintenance of the site, but it is not denied that it can be stolen by anyone other than the site administrator, if the holder of these cookies links a user identity to their cookieid, and the user name and address can be identified using this profile information. These cookies are embedded in HTML information and are passed back and forth between the user's machine and the site server, which can be dangerous if the user's registration information is not encrypted. As a result, many people believe that existence is a potential threat to personal privacy.

Because you didn't send a signal to the server that you have logged out, the server will record that you are logged in!

The login page can record your login information with a session.

This way you can know if you are logged in. It will be invalid for a long time.

HTTP (Hypertext Transfer Protocol) is a protocol used to transfer hypertext from a WWW server to a local browser. It can make the browser more efficient and make the network transmission less.

The address we type into the address bar of the browser is called the URL (Uniform Resource Locator). Just as every home has an address, every web page has an Internet address. When you enter a URL into your browser's address box or click on a hyperlink, the URL determines the address you want to browse.

Features of the HTTP protocol.

1. Simple and fast: When the customer requests services from the server, they only need to send the request method and path. Commonly used request methods include, and post.

Each method specifies a different type of contact between the customer and the server. Due to the simplicity of the HTTP protocol, the program size of the HTTP server is small, so the communication speed is very fast.

2. No connection: The meaning of no connection is to limit the processing of only one request per connection. Once the server has processed the customer's request and received a response from the customer, it disconnects. In this way, you can save transfer time.

Differences

HTTP is the most widely used network protocol on the Internet. www stands for the World Wide Web (also known as "web", "www", "w3.").'"World Wide Web" in English) is a system of many interlinked hypertexts, accessed via the Internet. These resources are delivered to users via the Hypertext Transfer Protocol, which in turn obtains them by clicking on a link.

All www files must comply with this standard.