What is blockchain? and why to use it?
We use a middleman (Banks) to facilitate financial transaction because we trust that the banking system is keeping accurate and up-to-date records. Blockchain is a replacement of this middleman.
Blockchain technology provides a historically consistent data store, that has multiple sources. In blockchain data is not allowed to be updated or modified after it is recorded and will never virtually be deleted. Think of it as you can't change history.
If the data is sensitive or has level of confidentiality, it should not be written to blockchain, even if it is encrypted. If the data doesn't require a specific trusted control or write access, or it's control authority can't be set or agreed between the multi entities who are providing the data, then blockchain is a solution. Blockchain is used for keeping an audit trail for data writing and timing.
A blockchain is made up of two primary components: a decentralized network facilitating and verifying transactions, and the immutable ledger that the network maintains. Everyone in the network can see this shared transaction ledger, but there is no single point of failure from which records or digital assets can be hacked or corrupted.