Ok, I'll pop back to answer that question - SWIFT is a financial messenging system. (Acronym of Society for Worldwide Interbank Financial Traffic - or some such). It's used by banks and related outfits simply because they had the need for such a thing.

Each msg has a header that identifies the recipient. I forget how its formatted but a bit like your International bank number (IBAN) on your statement/details.
With BTC it probably only includes the wallet ID (which is longer and more complicated! than an IBAN. There will be standards just the same to be sure of security and accuracy. I haven't looked how it's formatted but it is verified before being sent out. It may include time-zone stuff and other things.

Anyway, just the basis and I have to admit that's all I know.

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