Part 9/12:
Users open channels by locking up Bitcoin in a multi-sig. They interact off-chain via signed state updates, which can be revoked or contested if disputes arise.
The network supports multi-hop routing, allowing payments between users who do not have a direct channel.
While conceptually complex—requiring understanding of channel states, secrets, and time locks—future wallets and service providers aim to abstract these complexities away, making Lightning more user-friendly.
Risks:
Channel griefing or force-closing attack if parties behave maliciously.
Need to periodically watch the chain or rely on watchtowers that guard against theft or fraud.