This warning appears when promises are not properly handled. Adding error handling resolves it.

The 'Unhandled Promise Rejection' warning occurs when a promise encounters an error that isn’t caught, leaving the application vulnerable to unexpected behavior. To handle promises safely, attach .catch() to every promise or use a try-catch block when working with async-await syntax. Ignoring rejections can lead to application crashes or data inconsistency, especially in server applications. Updating Node.js to version 15 or above provides an option to automatically terminate the process on unhandled rejections, reducing the risk of silent failures, though this is best for development environments. It’s also helpful to implement centralized error handling for async functions, which can log errors consistently and reduce forgotten rejections. For larger applications, creating a wrapper function for async handlers helps ensure that any rejected promises within routes or middleware are captured. Adopting a rigorous promise-handling strategy not only improves code reliability but also prevents the accumulation of unhandled errors over time.