Does each satoshi have a unique identifier?
Bitcoin Ordinals protocol
( launched in 2023, just DYOR) allows to inscribe each individual satoshi and set to them the unique identifiers. Those satoshes can be traced (
with the relevant wallet app, like Ordinals Wallet) and traded . Moreover some people believe that so called rare satoshis are more valuable that other ones and sell/buy them on overestimated price. I'm not in their class and believe that all satoshis are equal in their value.
Ordinals is not a "Bitcoin protocol" it is a centralized and separate thing and the only link it has to bitcoin is that it is spamming the chain with arbitrary data. It is also not exactly inscribing satoshis, it is just injecting an arbitrary data into the chain which is an abuse of the Bitcoin protocol and its blockchain.