what is the threading system of flutter

Question

I have coded in dart and flutter for the past 3 months. I have one app in the play store. But I still don't understand how threading system of flutter works.

To make things simple let's take the most basic counter app that you get when you do flutter create basicapp.

Question no 1. How many threads are there in that basic app?
Question no 2. If there are multiple threads when are they created? When it calls runApp(MyApp())?
Question no 3. I know that dart has a concept of isolates. Are isolates the same as threads?

Answer 1

Question 1:

When the application starts running, there is a single Isolate/Thread that we know as the UI thread.

Question 2:

Generally you are good with a single thread in most applications. But in case you want to create a separate Isolate, you can use "Isolate.spawn". Provided a link in the end for better understanding.

Question 3:

Answering simply, Yes.

Here is a link for better understanding.

Cheers!! Hope it helps.