In Mastering Bitcoin, it says:
The transaction is then broadcasted on the bitcoin network, where each network node (participant) validates and propagates the transaction until it reaches (almost) every node in the network. Finally, the transaction is verified by a mining node and included in a block of transactions that is recorded on the blockchain.
I assume that nodes are using public keys to validate a digital signature, but what do miners do? I know that they are solving a hash puzzle to find the nonce that generates a certain pattern of a hash value but are they verifying something here?