this is probably the noob-question of the day:

So I've written this game.

Now there's the .exe file that does the work, a folder with my beautiful, beautiful assets and a bunch of .dll files and other stuff that I probably shouldn't touch. To run the game, I copy the whole lot to the desired computer, double-click the .exe file and start shooting some dudes. Yay!

But what exactly is the difference between that and using an installer? What else does an installer do besides copying files and looking more professional than a .zip-file? Is there generally a lot of patching/configuring involved when trying to make a game run on a different computer? I tested my game on all windows computers I could get my greedy fingers on and it works great.

Thanks for your time.