The key differences between Runnable and Callable are:

  • Return Value:
    • Runnable: Does not return a result or throw an exception. Its run() method is void.
    • Callable: Returns a result and can throw exceptions. Its call() method returns a value of type V.
  • Exception Handling:
    • Runnable: Cannot throw checked exceptions in the run() method.
    • Callable: Can throw checked exceptions in the call() method.
  • Use Case:
    • Runnable is used for tasks that do not require a result and do not throw checked exceptions.
    • Callable is used for tasks that need to return a result or handle exceptions.

In summary, use Runnable for simple tasks without a return value, and use Callable for tasks that need a result or may throw exceptions.