Description: The preflight request, in the context of CORS (Cross-Origin Resource Sharing), is a security mechanism that allows browsers to verify whether a cross-origin request is safe to send to the server. When a web application attempts to make a request to a different origin than the one that served it, the browser first sends a preflight request using the HTTP OPTIONS method. This request includes information about the HTTP method and headers that will be used in the actual request. The server, upon receiving this request, must respond with the appropriate headers indicating whether the actual request is allowed. If the server responds affirmatively, the browser will proceed to send the actual request. This process is crucial for protecting users from attacks such as Cross-Site Request Forgery (CSRF) and ensuring that requests are only made to servers that have been explicitly authorized. The preflight request is an integral part of the CORS protocol and helps maintain the security and integrity of modern web applications, allowing for secure communication between different origins.
