Blockchain technology, or distributed ledger technology (DLT), as it is alternatively often called, is one of the hottest topics in the technology sector as of now. A blockchain is a specific type of distributed ledger that stores data in blocks that are linked together via a cryptographic signature function.
This, in short, works by always using the signature of the last block plus the data of the current block to sign the current block. Given enough computing power behind creating the hash signatures for new blocks, a process that is known as mining (PoW), the resulting public ledger is virtually unmodifiable for malicious actors, commending itself for applications that rely on mutual trust where trust cannot be easily applied.
musings of a consultant 