Application Settings

I'm new to this, or precisely just realize that visual studio had this in the properties folder below visual studio project.
I'm planning to put important things like connection strings inside.
I tried to save a simple text in the setting and save it.
When I run the application, in the debug folder appear "WindowsFormsApplication1.exe.config" file.
I know that it's the setting I created, but the value of the setting is not inside.
When I re-run the application, it was able to load the text i saved before.
Where did the setting save the value? http://www.barakasoft.com/script/For...smiley_OMG.gif
Btw sorry for bad english.