LNURL works by using HTTP requests to do things like:

• LNURLw: ask a server to pay an invoice (server tells you that you must send an invoice of min <= x <= max sats, you send one, payment made)
• LNURLp: ask a server for an invoice (server tells you that you can request an invoice of min <= x <= max sats, you request, you get an invoice to pay)
• LNURLauth: sign a message the server sent for authentication (server tells you to sign a message, and your client signs a message with the domain of the service, and the data provided)