What is meant by payload in the context of HTTP requests or APIs?

Payload in the context of HTTP requests or APIs is the data that is transmitted in the body of the request or response. For example, when sending a POST request to a server, the payload may contain JSON with information that needs to be stored or processed. In GET requests, payload is usually absent, and data is transmitted via URL parameters.

Example of a POST request with a JSON payload:

{
  "username": "user123",
  "password": "passw0rd"
}

This JSON is the payload that the server receives and processes.