Merkle Trees (also called Hash Trees) are binary data structures that are fundamental for the existence of blockchain technology; actually this is the very technology that allows for the existence of “chain” in blockchains.
Deriving its name from its appearance, Merkle Trees leverage cryptographic hashes to create proofs and paths of activities that take place. In a Merkle Tree, every single point/node/leaf points to 2 possible child leaves and each one of those child leaves points to 2 more possible child leave, in turn creating a linked list of what is true and what isn’t. The leaves are organized and sorted through the hashes which they represent.