Newbies in Android face difficulty with communicating between different threads. It is better to create a new background thread instead of delaying the UI thread when there is lengthy task. Let us say you want to read an html file. If you read this file in UI thread, the program appears to be unresponsive. Hence it is better to read the file in a background thread. But when this reading is completed, how do you show the html in a webview in this example? The background threads can not access the ui widgets. Hence there is a need to communicate between ui thread and background thread. This can be done with Handlers. Handlers are used to send and process messages. A handler created in a thread, can process all the messages sent by this thread. You should create a handler class for processing messages private class MyHandler extends Handler{ @Override public void handleMessage(Message msg) { if(msg.getData().getString("message").equals("y...