# Introduction to Validators
Validators play a key role in running Unification's Mainchain. Mainchain is built on Tendermint, which relies on a set of defined validator nodes to process transactions and produce and sign new blocks.
The initial validator set for MainNet is 96, and is selected from the validators who have the most FUND delegated to them through a combination of self-delegation, and user delegation.
Validators earn rewards from transaction fees, and commission charged to their delegators.
Validator operator candidates are expected to thoroughly research security for their nodes to ensure the overall safety of the network.
For further information, see becoming a validator, AWS 101, Google Cloud 101.