What is the difference between a node and a miner?

A miner produces new blocks by doing proof-of-work with a CPU or GPU and competes for the block reward. A node validates and relays whatever miners produce: it checks every block against the consensus rules and rejects anything invalid. The two jobs are distinct. A node does no mining and earns no coins; it secures the network by enforcing the rules. Many miners run a node so they have a trusted local view of the chain, but you can run a node without ever mining a single hash. Miners propose blocks, nodes decide which ones count.