Take you in-depth understanding of cookies

This article only introduces some basic knowledge of cookies and the components that make up cookies, and does not introduce usage.

What the heck is a cookie?

Cookie, the introduction in Baidu Baike refers to "data stored on the user's local terminal",In human terms, it is similar to a browser's local cache, which is a piece of text that a website uses to identify a user.Generally speaking, when we open a website, the web server of the website will generate an ID information for the user. It can be said that this is the user's network "ID card", and then this "ID card" will be saved locally on the user's computer.If the user logs in to the website again, the web server can read the text and obtain various information about the user. This process is login.

Cookie sending mechanism

In general, whenever we log in to a website for the first time, the web server will send a cookie to the user's local, and in subsequent logins, the user's local cookie will be sent to the web server to verify theirAccount, represented by an image:

The composition of cookies

Cookies are essentially text data. Generally, this data is encrypted and consists of name, value, and several equivalents used to control the scope of use or valid time of the cookie.

• Name and Value Name/Value: The name and value of the cookie.
• Expires Expires: The expiration date of the cookie.Expriers are divided into two types of storage: session and persistent.Session cookies are stored in the user's memory and are cleared when the browser is launched; persistent cookies are stored on the user's local hard drive and will not expire until the user logs out.Speaking human words is a temporary storage, a long-term storage.
• Scope of use Domain: The scope of use of cookies.
• Security Secure: Whether the cookie uses the Https protocol.

Summary

Cookie is the data (encrypted) that the website uses to identify the user and saved on the user's local area. It is the text data temporarily or permanently saved locally by the user, and generally consists of name, value, validity period, and scope of use.