Blockchain is a technology that runs bitcoin. Bitcoin is a revolutionary cryptocurrency which is a digital payment system running on the blockchain technology. Blockchain is shorthand for a whole suite of distributed ledger technologies that can be programmed to record and track anything of value from financial transactions,medical records and land titles.
Blockchain stores the information in batches called blocks that are linked together in a chronological fashion to form continuous line metaphorically,a chain of blocks. If you make a change to the information recorded in a particular block,you don’t rewrite it, instead the change is stored in a new block showing the ‘x’ changed to ‘y’ at a particular date and time.
Blockchain was designed to decentralized and distributed across a large network of computers.This decentralized information reduces the ability for data tampering.Before a block added to the chain a few things has to happen
- A cryptographic puzzle must be solved ,thus creating the block.
- The computer that solves the puzzle shares the solution to all the other computers on the network. This is called proof-of-work.
- The network verifies the proof-of-work and if correct block will be added to the chain.
Blockchain is a type of technology not a single network,it can be implemented in many different ways.Some blockchains can be completely public where everyone can view and access it.Others can be closed to a authorized users such as company,group of banks and there are hybrid public-private blockchains. Blockchain makes things transparent, democratic, decentralized ,efficient and secure.