What is Blockchain?
Blockchain appears to be complex, and it can certainly be, but its basic principle is very simple. A blockchain is a database form. To be able to understand blockchain, it makes you first understand what the database really is.
Blockchain is a particular database type and it differs from a traditional database in the way it stores information; blockchains store data in blocks that are then chained together. When new data comes in, a new block is entered. Once the block is filled with data, it is chained to the previous block, making the data chained together in sequential order. Different types of information may be stored in a blockchain, although the most common use has been digital ledger for transactions.
The decentralized database, operated by many participants, is known as Distributed Ledger Technology (DLT). Blockchain is a type of DLT, where transactions are listed with an irreversible cryptographic signature which is called a hash. This implies that if one block in one chain had been modified, it would be instantly obvious that it had been tampered with. If hackers were to corrupt a blockchain system, they would have to change every block in the chain through all the distributed versions of the chain. Blockchains such as Bitcoin is increasing consistently as blocks are added to the chain, which contributes significantly for the protection of the ledger.
In the case of Bitcoin, blockchain is used in a decentralized manner such that no single individual or community has power—rather, all users collectively maintain control. Decentralized blockchains are permanent, which implies that the entered data is irreversible. For Bitcoin, this ensures that transactions are permanently registered and accessible to everyone.