CompletableFuture is a class in Java that simplifies asynchronous programming. It allows developers to write non-blocking code, meaning tasks can run in the background while the main program continues executing. This is particularly useful for improving application performance, especially when dealing with tasks like network calls or file I/O. With CompletableFuture, you can easily combine multiple asynchronous tasks and handle their results once they complete. It provides methods for chaining tasks, handling exceptions, and waiting for multiple futures to complete. This makes it a powerful tool for building responsive applications that can efficiently manage concurrent operations.