How can my application share it's resources with another client? This is where the CORS, or Cross Origin Resource protocol comes in. CORS introduces a standard mechanism that can be used by all browsers for implementing cross-domain requests. The spec defines a set of headers that allow the browser and server to communicate about which requests are (and are not) allowed. CORS continues the spirit of the open web by bringing API access to all. What is a cross-site request? Cross-site HTTP requests are HTTP requests for resources from a different domain than the domain of the resource making the request. Such requests are subject to security-based restrictions. To handle this restrictions, and get around them in a secure manner, W3C developed CORS. What is CORS? The Cross-Origin Resource Sharing (CORS) mechanism provides a way for a server to support cross-site requests and enable the secure transfer of data across different domains/sites. How can our Rails AP...