A mainnet is a fully functional, active blockchain. Mainnet blockchains properly validate transactions and consist of immutable, distributed ledgers that everyone can examine openly. Mainnets are operational and trade "actual" cryptocurrencies having monetary value, as opposed to testnets, which exchange symbolic, worthless coins. After testing and revising their projects and updates on testnets, developers launch them to mainnets. The principal blockchains of Ethereum and Bitcoin are both examples of mainnets.