Block

A block is a package of data that contains zero or more operations, a hash to the previous block and other data. We call it blockchain, because each block points to a previous block, except for the very first block: the genesis block.

Good to know

A block is uniquely identifiable by its hash. In Tezos the block's hash is prepended with the letter B as defined here. A valid example is BLCvke7kTB12jEs8tNQukMbCmkknwnfSDQwmZKniKwbQ2yJJb6W.