Thread vs Runnable? Which is better?

Extending Thread:

• Limited by single inheritance (you cannot extend another class).

Implementing Runnable:

• Better: Leaves your class free to extend another class.
• Supports better separation of task (the code in run()) and worker (the Thread instance).
• Ideal for use with ExecutorService.

Runnable as Lambda:

Thread t = new Thread(() -> System.out.println("Running..."));
t.start();