Block

A block is the smallest element of a blockchain; the first block is called the genesis block. Each block contains batches of hashed and encoded transactions. The blocks are stored in a Merkle tree formation. Every block includes the hash of the previous block in the chain that links all blocks to one another. In Bitcoin, a block contains more than 500 transactions on average. The average size of a block is around 1 MB. A block is comprised of a header and a list of transactions.