Block top - The block amount and size 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 actually be the 101st transaction submitted by this account) https://social-lyft.com/story10739163/blockchain-explorer-fundamentals-explained-https-www-udrpsearch-com-user-lampwhorl2