X-Content-Type-Options: 'nosniff' Header for Security

X-Content-Type-Options is a HTTP response header used to prevent the browser from automatically interpreting the response content type. The value 'nosniff' is a directive of this header, instructing the browser to not override the declared content type and to not sniff the response content type.

When a browser receives a response from a server, it attempts to determine the content type by inspecting the response headers and the content itself. This can lead to security vulnerabilities if the browser interprets the content in an unintended way.

By setting the X-Content-Type-Options header to 'nosniff', the server tells the browser to strictly follow the declared content type without attempting to sniff or interpret it. This helps prevent certain types of attacks, such as MIME type sniffing, Cross-Site Scripting (XSS), and content injection attacks.