Java Callable<T> is a functional interface that represents a task that can be executed asynchronously and returns a result or throws an exception. Unlike the Java Runnable interface, Callable can return a value and handle exceptions, making it ideal for tasks that need to compute and return results in a multithreaded environment. Introduced in Java 2004 with Java 5, Callable is part of Java's java.util.concurrent package and is often used in conjunction with Java ExecutorService for concurrent task execution.

https://docs.oracle.com/javase/8/docs/api/java/util/concurrent/Callable.html