Block top - The block selection and duration on the blockchain (in blocks) on generation of the present block Nonce - The transaction selection for the from address (bear in mind this starts at 0 so a nonce of 100 would really be the 101st transaction submitted by this account) https://bookmarkmoz.com/story20833854/blockchain-explorer-fundamentals-explained-https-gaiaathome-eu-gaiaathome-show-user-php-userid-1577569