Add-ons are scripts with extra 'boilerplate' and 'interface' code added. The extra code is for giving Blender a way to automatically load the add-on and have it load in the right places (menus) or appear in the right context (in edit mode for example).
Blender now has great docs showing best practices for approaching add-on code. The page also links to additional Python tutorials that cover the level of Python that you will need to be able to write stable add-ons. Even if your goal is to only write Blender add-ons, learning Python as fully as possible will never be a waste of time.
That tutorial shows how to register addons / operators and how to define and remove user defined keyboard shortcuts. I think most of that code is not obvious until you see working examples, and you experiment with dummy add-ons. Just like with the Operators programming page on this wiki I'll suggest you read more closely the content of Blender's /addons folder. If you've followed the above tutorial then seeing real add-ons with already working code will quickly reinforce the concepts.
- Not all scripts need to have full blown add-on code straight away. Sometimes you'll write a script for a specific task and never use it again or only use it 2 years later. Infrequently used scripts like that don't need add-on code (if you can get away with it).