GET v POST Why is it better to use a POST request than a GET request if some data sentalong with the request is confidential?

When dealing with confidential data, it's generally better to use a POST request over a GET request for several reasons:

1. Data Security: In a GET request, the data is appended to the URL as query parameters and is visible in the browser's address bar. It's also stored in browser history and server logs in plain text. A POST request, on the other hand, sends data in the body of the HTTP request, which is more secure and doesn't expose the data in the browser's address bar or store it in browser history.

2. Data Size: GET requests are limited in size because they are sent in the URL. Most browsers limit URL lengths to around 2000 characters. POST requests, however, have no size restrictions because the data is sent in the body of the request, making them more suitable for sending large amounts of data.

3. Data Type: GET requests can only send data as ASCII characters. POST requests, however, can send binary data and ASCII characters, which makes them more versatile.

4. Idempotency and Safety: GET requests are idempotent and safe, meaning they can be cached, bookmarked, and can be repeated without side effects. POST requests are neither safe nor idempotent. They change the server state and have side effects when repeated. This makes POST requests more suitable for sending confidential data because they won't be cached or bookmarked.

5. Semantic Correctness: According to the HTTP/1.1 spec, GET requests should be used to retrieve data and should not have side effects. POST requests should be used when a request is intended to change the server's state. So, when sending confidential data, a POST request is semantically the correct choice.

In conclusion, while both GET and POST requests can be used to send data, POST requests provide a more secure, versatile, and semantically correct option for sending confidential data.