BitPoin is an app to get you started using bitcoin on the Lightning Network, bitcoin's 2nd layer network that optimizes speed, transaction volume and fees. Like kilometers and millimeters, sats or also known as satoshi, is the smallest fractional unit in Bitcoin. There is 100.000.000 sats in 1 bitcoin. So rather than saying 0.000001 bitcoin, you can just say 10 sats (satoshi) The Lightning Network is the 2nd layer of the Bitcoin network. Whereas the 1st layer of Bitcoin is optimized for security, Lightning Network is used to improve speed and micropayments capabilities.