Off-chain transactions that take place may later be reported or bundled together before being sent to the main chain.
Node
An essential component of a blockchain infrastructure, a node stores data and allows all communication (transactions) to pass through it.
Candidate Block
In a few words, a candidate block is a block that a mining node (miner) is trying to mine in order to receive the block reward. So a candidate block may be described as a temporary block that will be either validated or discarded by the network. Miners compete with each other to validate the next block and add it to the blockchain, but first, they have to create a candidate block to participate in the mining competition.
Governance Token
Developers design governance tokens to let token holders influence the direction of a protocol.