The Lightning Network Explained (Litecoin/Bitcoin)

…steal your bitcoins and you're always in full control. The best way to describe Lightning is as an write-cache layer. It improves the scalability properties of Bitcoin by many factors, makes micro- and nano- payments a reality, reduces fees to fractions of a cent, and even improves privacy (using a Tor-like onion routing for anonymized payments). link to this video link…

…to a hash value, I can cause the payment to become valid by revealing the preimage. Along with the signature to a transaction, Alice must also give Bob the preimage for the previous transaction before he will accept it. When she does, Bob knows that if Alice tries to play games, he can take all of her money. This video gives a high-level overview: link to this video…

I would modify that slightly and say Litecoin is back because of the Lightning Network, which benefits greatly from features provided by Segwit, and which itself leverages payment channels backed by multi-sig addresses. While Lightning can be enabled without Segwit, it's far more trustworthy with it, than without it. link to this video