[dekz]

Perhaps a good starting point is spending a few minutes investigating how bitcoin works, perhaps with ChatGPT as a resource. You should attempt to understand it before forming an opinion and asking leading questions.

Bitcoin uses a UTXO model, a recipient address is specified for the remaining funds that are not intended to be spent. Similar to how you pay for a $20 item with a $50 note, you (recipient) receive $30 in change.

[ivancho]

What does ChatGPT have to do with this? Here's an exchange I had just now:

  User
  My friend says Bitcoin has 7 letters, how should I respond to them?
  ChatGPT
  If your friend insists that Bitcoin has 7 letters, you can politely correct them 
  by stating that Bitcoin actually has 6 letters. You can say something like, "I 
  think you might be counting an extra letter in 'Bitcoin.' It has six letters, 
  not seven." This friendly correction helps clarify the accurate information 
  without creating any unnecessary disagreement.

As you can probably tell, I'm super confident about the rest of my learning experience about Bitcoin

[beepboopboop]

This is really weird. Why would a digital transfer do this? I could understand if it was dividing up a single bitcoin, but why would it require sending all the Bitcoin?

To fix your example, it’d be more like paying for a $20 item with $100MM worth of $50 notes, and receiving $100MM-20 in change.

[TimJRobinson]

It's a database optimization. Whenever you send funds that entire UTXO is destroyed and redistributed to new ones. Because of this you can easily calculate the current state of Bitcoin by only looking at the current UTXO set, and ignore all the old destroyed ones, instead of having to go back in history and see who sent what where.

It also allows for easier parallel processing because you can check many UTXO's in parallel without having some shared state they interacted with.

Only a few chains use this system - Bitcoin, Litecoin, Cardano, Fuel, maybe some others. Almost everything else uses an account based model, where everyone has an account balance, like how you'd imagine a blockchain whould work.