HTTP is a protocol based on the client-server model. The common HTTP request methods are GET and POST. The main differences between them are as follows:
Request method
GET: used to request the server to return a specified resource. Request parameters are passed through the URL, appearing in the URL as query strings.
POST: Used to submit data to the server and request the server to accept the entity contained in the request as a new subresource. Request parameters are passed through the body part of the HTTP request.
Request parameters
GET: The request parameters are passed through the URL and appear in the URL in the form of a query string. The query string contained in the URL has a length limit, and the parameters are not very safe, because the parameters in the query string can be stored in the cache, history records, etc., and are easy to be obtained by malicious users.
POST: Request parameters are passed through the body part of the HTTP request, so any data type can be passed, and the size is not limited. The request body is usually encoded in a form, but other formats such as JSON or XML can also be used. The parameters in the POST request are safer than the GET request, because the request parameters will not be saved in the browser's history.
Cache
GET: Requests can be cached, and browsers can reduce network requests and improve performance through caching.
POST: The request will not be cached, and data will be sent to the server every time a request is sent.
Security
GET: The request is not very secure, because the parameters in the query string can be stored in the cache, history records, etc., and are easily obtained by malicious users.
POST: The request is more secure than the GET request, because the request parameters will not be saved in the browser's history, and the HTTPS protocol can be used for encrypted transmission to improve data security.
To sum up, the main difference between GET and POST requests lies in the request method, request parameters, cache and security. In practical applications, it is necessary to select an appropriate request method according to specific business scenarios and requirements.