Cross Origin Resource Sharing

Cross Origin Resource Sharing (CORS) is a security mechanism implemented in web browsers that allows web applications running at one origin (domain, protocol, and port) to request resources from a different origin. It uses HTTP headers to define which origins are permitted to access resources, enabling controlled cross-origin requests while preventing unauthorized cross-site requests. CORS is essential for modern web applications that rely on APIs and services hosted on separate domains.

Also known as: CORS, Cross-Origin Resource Sharing, Cross Origin Sharing, Cross-Origin Requests, Cross Domain Requests

Why learn Cross Origin Resource Sharing?

Developers should learn CORS when building web applications that need to make requests to APIs or services on different domains, such as single-page applications (SPAs) using a separate backend API, or when integrating third-party services. It is crucial for security compliance, as browsers block cross-origin requests by default, and understanding CORS helps prevent common errors like 'Access-Control-Allow-Origin' issues and ensures proper data sharing between origins.

Learning Resources

• docs: MDN Web Docs: Cross-Origin Resource Sharing (CORS)
• video: CORS in 100 Seconds (Fireship)
• tutorial: CORS Tutorial (freeCodeCamp)
• tutorial: Understanding CORS (Auth0 Blog)
• course: CORS Course (Pluralsight)