Thread.Sleep vs Task.Delay?

The documentation on MSDN is disappointing, but decompiling Task.Delay using Reflector gives more information:

public static Task Delay(int millisecondsDelay, CancellationToken cancellationToken){    if (millisecondsDelay < -1)    {        throw new ArgumentOutOfRangeException("millisecondsDelay", Environment.GetResourceString("Task_Delay_InvalidMillisecondsDelay"));    }    if (cancellationToken.IsCancellationRequested)    {        return FromCancellation(cancellationToken);    }    if (millisecondsDelay == 0)    {        return CompletedTask;    }    DelayPromise state = new DelayPromise(cancellationToken);    if (cancellationToken.CanBeCanceled)    {        state.Registration = cancellationToken.InternalRegisterWithoutEC(delegate (object state) {            ((DelayPromise) state).Complete();        }, state);    }    if (millisecondsDelay != -1)    {        state.Timer = new Timer(delegate (object state) {            ((DelayPromise) state).Complete();        }, state, millisecondsDelay, -1);        state.Timer.KeepRootedWhileScheduled();    }    return state;}

Basically, this method is just a timer wrapped inside of a task. So yes, you can say it's just like timer.