There are no dumb questions. May be considered dumb the questions that already have been answered 10 times and explained in videos tutorials !!!
Your question is important and have not been asked yet.
We call alias, a formated string that is composed only of lowercase letters, no spaces, no quotes...
If you look in the url of this topic, you can see : what-is-the-alias-for
It comes from the title : What is the alias for ?
Well, the wizard allows you to automatically save the title (for example), in a such format string.
For the moment it does not use it in the url rewritting. In fact, the alias is not used for nothing.
Maybe you was searching for a special functionality, but there isn't.
Once your alias field beeing initializated, you can reuse it for any purpose you want (url, file name, folder name, etc...)