Could someone point me to or provide a description of what the various fields are in a block?
2 Answers
https://tezos.gitlab.io/008/rpc.html#get-block-id
https://mainnet-tezos.giganode.io/chains/main/blocks/head
Most fields, IMO, are semi-self-explanatory by their name depending on what you are looking for.
See also here this section of the documentation: https://tezos.gitlab.io/008/proof_of_stake.html#blocks