I have done some research on this topic . the [thread](https://stackoverflow.com/questions/18260786/updating-gui-form-elements-continuously-so-that-form-does-not-hang) at SO also caught my interest and I wanted to summarize my understanding and be corrected if I am going wrong on a certain path and also wanted to know how QueuedConnection would work.

Here is my understanding followed by the question.
Signals can be connected manually to slots primarily through two different ways first way is using direct connection and the second way is queued connection. In case of a direct connection if the slot method that is attached to the signal is in the same thread then the slot method is called sequentially (as if it was just another method) however incase the slot is in a different thread from where the signal is launched then QueuedConnection would launch it when it finds it appropriate. (Now In this case I am not sure if it would launch a new thread or how it would proceed on doing that)