Lightning doesn't have blocks, so there are no lightning "block explorers," and consequently, as devs, if we make a third party website where one person can pay another, it can be difficult to check whether the payment went through. Often we want to know information like "Did this payment succeed?" and there's just nowhere to look.

To fix this, we mostly have to make do with self-reporting by either the sender or the recipient. NWC is a standardized api for that. It also has some other features, like the ability to remote-control a wallet (if the owner gives you permission) and thus remotely "click" the Send and Receive buttons.

Learn more here: https://nwc.dev/