Blockchain is one of the hottest topics in technology and finance sector today. From insurance to logistics, real estate to healthcare — blockchain is predicted to transform almost every single industry in the next ten years. That is why it is important to understand what blockchain is.

In simple terms, a blockchain can be described as an append-only transaction ledger. What that means is that the ledger can be written onto with new information, but the previous information, stored in blocks, cannot be edited, adjusted or changed. Basically, blockchain is a growing list of records, called blocks, which are linked using technology called cryptography.

An individual block in a blockchain contains the following elements: block number, data stored in the block, hash (or cryptographic hash) of the previous block and hash of the current block. Blocks hold batches of valid transactions. Each block includes the cryptographic hash of the prior block in the blockchain, linking the two. The linked blocks form a chain. This iterative process confirms the integrity of the previous block, all the way back to the original genesis block. Each block contains a cryptographic hash of the previous block, a timestamp, and transaction data.