What is CORS, and how can it cause Axios network errors in a React Native Android application?

CORS (Cross-Origin Resource Sharing) is a security mechanism implemented by web browsers to restrict web pages from making requests to a different domain than the one that served the web page. If your React Native app is making requests to an API on a different domain, and the API doesn't have the correct CORS headers configured, Axios requests will be blocked by the browser's security policy, resulting in a network error. The server needs to include appropriate `Access-Control-Allow-Origin` headers in its responses.