# Polkadot Nodes

A node is a peer in the peer-to-peer network. Nodes communicate with each other to reach consensus on the state of the network. Within Polkadot there are several types of nodes having different configurations:

**Archive node**: nodes that store the complete history of the blockchain. In other words, all the blocks and their representative states of the chain.

**Full node**: nodes that store all of the block headers and the latest 256 blocks.

Both the archive node and full node can have specific configurations enabled/disabled:
- **Block producing nodes**: nodes that produce blocks (the value propisition for running a node). For the relay chain these are validators (which includes contributing to GRANDPA), and for parachains these are collators. Their specific role is different in the overall Polkadot protocol, but at an abstract level, you can think of them both as block producers.
- **Boot nodes**: nodes who have their networking address publicly available. These nodes are required for new nodes to join the peer-to-peer network.
- **RPC nodes**: nodes who expose their RPC endpoints. Blockchain applications can use these nodes to qeuery data from the blockchain.

RPC and bootnode configurations often come hand in hand.

**Light nodes**: nodes that are specifically designed to fastly sync with a chain from scratch and store as little data possible.
- **Read-only light nodes**:
- **TODO**:
https://getblock.io/blog/types-of-nodes-in-blockchains/