async and Task vs Thread

I have seen examples where they create a new Thread for not block UI, but this way we don't have the progress of process, also you have to process the response within the Thread because the run() method doesn't returning anything. AsyncTask seems better option than Thread, but I don't know what are the consequences of using an AsyncTask instead of a Thread. Moreover, AsyncTask is a special kind of Thread - one which is a GUI thread, it works in the background and also let's you do something with the GUI - it is basically "pre-programmed" for you with functions onPreExecute(), do inBackground(), onPostExecute(). In order to make Thread work that way, you have to write a lot of code.