# What is Mainchain?
Mainchain is the backbone of the Unification Network. It is a Tendermint based chain, and is where WRKChains and BEACONs submit their hashes, and FUND transactions take place.
Mainchain is a public proof-of-stake chain. The core coin used for staking, rewards, and network fees is FUND. The on-chain denomination is
nund(Nano Unification Denomination) which is 10^-9 FUND.
There are currently two live public Mainchain networks, and one private development network:
Launched on 14/05/2020, FUND-Mainchain-MainNet is the live public Unification Main Network.
Launched in Q4 2019, FUND-Mainchain-TestNet serves as the official Unification public Test network, where developers can test WRKChains/BEACONs or third party application ssuch as wallets and block explorers before deploying on MainNet. It also serves as a test platform for Mainchain developers to test updates and new features to the Mainchain code in a live environment.
The Mainchain suite comes with two binaries:
und- "Unification Daemon": the Mainchain server-side daemon, used to run a full node for Mainchain. Validators run this service to produce blocks. See full command reference
undcli- "Unification Daemon Client": the command line interface for interacting with Mainchain nodes. It can also be used to run a light-client RPC node service. See full command reference
Mainchain has been built with the following core Cosmos SDK modules:
x/auth: Accounts and signatures.
x/bank: Token transfers.
x/staking: Staking logic.
x/distribution: Fee distribution logic.
x/slashing: Slashing logic.
x/gov: on-chain governance logic.
x/supply: FUND Coin supply logic
x/params: Handles module-level parameters, which can be modified via governance.
x/crisis: Handles potential network errors during the early days of deployment
Unification have also developed the following modules for Mainchain:
x/beacon: BEACON hash timestamp submission logic
x/enterprise: Handles purchasing, locking and unlocking of Enterprise FUND
x/mint: A modified core Cosmos SDK module, handling inflation and Block Reward logic.
x/wrkchain: WRKChain block hash submission handling
Installing the Mainchain binaries