Validator
Plain English
Think of validators as referees in a sports game. They check that all transactions are legitimate, follow the rules, and record them correctly. They stake their own money as a guarantee they’ll be honest - if they cheat, they lose their stake.
Technical
A node in the network responsible for validating transactions, producing blocks, and maintaining consensus. Validators stake SOL tokens as collateral and earn rewards for honest participation. On Solana, they vote on blocks using Tower BFT consensus and process transactions using Turbine block propagation and Gulf Stream mempool.