What is WebLN
WebLN is a set of specifications for Lightning apps and client providers to facilitate communication between web apps and users' Lightning nodes in a secure way. It provides a programmatic, permissioned interface for letting applications ask users to send payments, generate invoices to receive payments, and much more.
WebLN Provider functionality
WebLN builds on the idea of web3.js, a collection of libraries that allow you to interact with a local or remote ethereum node using HTTP, IPC or WebSocket. The WebLN specifications were published in 2018 and since then have continuously improved. In the meantime several Lightning applications and client providers have been built using this standard.