Ethereum, Bitcoin, and other cryptocurrencies have a test (Testnet), as well as a main (Mainnet) network. What is the difference between them? Testnet is used at the early stage of project development, or if necessary, to test updates before they are added to the main network. The coins have no value in the test network. They are also not taken into account in the emission of this cryptocurrency. Run a closed or open Testnet. Mainnet is the main network of cryptocurrency, in which transactions with coins that have real value are carried out, as well as their mining. It is believed that a blockchain project moves into the finished product stage from the development stage after the launch of the main network.