Block top - The block number and length from the blockchain (in blocks) on creation of the current block Nonce - The transaction variety for that from address (Remember this starts off at 0 so a nonce of a hundred would actually be the 101st transaction submitted by this account) https://letsbookmarkit.com/story20489907/blockchain-explorer-fundamentals-explained-https-writeablog-net-storeformat0-blockchain-in-the-microscope-exploring-the-unsung-resources