Well done, you've learnt LocalStorage. It's pretty simple and not much to it really. Try not to rely on it too much, if you find yourself storing lots of data then you probably want to look at adding some kind of backend to your app, either with a server or a Backend As A Service like Supabase or Firebase.
It good to test your knowledge just after learning something new, it solidifies the connections in your mind and identifies any areas that you should go back over.
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