Medium of Exchange
economics · beginner
One of the three classical functions of money: the thing you trade for goods and services instead of bartering directly.
Money as a medium of exchange replaces n×n bartering with n×1 pricing. Historically, the asset that becomes the dominant medium of exchange tends to also be the dominant store of value — the two functions reinforce each other, though they can diverge during transitions.
For Bitcoin, layer-1 settlement is slow and fee-bearing — fine for large or final transactions, awkward for buying coffee. Lightning is the medium-of-exchange answer: payments settle instantly, fees are typically a few sats, and the underlying bitcoin is final on-chain whenever the channel closes. The two layers split the workload: L1 for value, L2 for velocity.
Network effects dominate adoption. A currency only works as a medium of exchange to the extent that other people accept it; this is a chicken-and-egg problem that took fiat decades to solve via legal tender laws. Bitcoin's path is bottom-up: payment processors, regional adoption (El Salvador, Lugano), Lightning-native services, and the slow accumulation of merchants who hold a balance instead of converting immediately.