Intro
Solana makes use of independent nodes which have the responsibility of working to confirm programs and outputs of programs on one of the three Solana clusters, Devnet, Testnet or Mainnet Beta. A cluster is made up of a set of validators that work to confirm transactions. These are owned and operated by individuals. These nodes are also responsible for storing data and transaction history which is shared amongst the nodes. A node can become a validator node if it is being used to vote on valid blocks and if SOL is delegated to the validator identity it can become a leader node. This is the link to the information on how to become a validator.
Not all nodes can become leader nodes or vote to confirm blocks. They still serve the other functionalities of validator nodes, but since they cannot vote they are primarily used to respond to requests on the blockchain. These are RPC nodes. RPC stands for remote procedure call, and these RPC nodes are used to send transactions through the blockchain.
Solana maintains three public API nodes, one for each cluster which are Devnet, Mainnet Beta, and Testnet. These API nodes are what allow users to connect to the cluster. To connect to Devnet users can use:
https://api.devnet.solana.com
This is the node for Devnet, and it is rate limited.