samesorigin

Samesorigin is a term used in web development to refer to the same origin policy. This security mechanism is a fundamental part of how web browsers protect users from malicious websites. The same origin policy dictates that a web page loaded from a particular origin can only interact with resources from the same origin. An origin is defined by the combination of the protocol (e.g., http, https), domain name (e.g., example.com), and port number (e.g., 80, 443).

If a web page attempts to access data or execute scripts from a different origin, the browser will typically block the request. This prevents a malicious script on one website from reading sensitive data from another website that a user is logged into, such as their bank account or email. For instance, a script on `evil.com` cannot directly access cookies or make HTTP requests to `yourbank.com` if the user is authenticated on both sites.

There are exceptions and workarounds to the same origin policy. For example, JSONP (JSON with Padding) was a technique used to bypass the policy for retrieving data from different domains, though it has security implications. Modern approaches like CORS (Cross-Origin Resource Sharing) provide a more secure and standardized way for servers to explicitly allow certain cross-origin requests. CORS uses HTTP headers to inform the browser which origins are permitted to access its resources. Web developers must understand and correctly implement these mechanisms to ensure both security and functionality in their web applications.