Block top - The block selection and size with the blockchain (in blocks) on generation of the current block Nonce - The transaction selection to the from address (bear in mind this commences at 0 so a nonce of a hundred would actually be the one hundred and first transaction https://bookmarkity.com/story20631419/detailed-notes-on-blockchain-explorer-unconfirmed-transaction-https-fletcher-odonnell-thoughtlanes-net-exploring-further-the-world-of-blockchain