Blockchain was initially made for a decentralized ledger of all Bitcoin trades which happen inside the Bitcoin network.
A decentralized or dispersed database/ledger basically suggests that the storage apparatus, in which the ledgers are, aren't connected to a frequent chip. You can choose Applicature to know more about blockchain development.
The blockchain comprises the ever-growing collection of trades by means of cubes. Each block is time-stamped and then connected into the prior block to be part of the blockchain.
Before computers, people kept their important documents safe by making lots of copies of them and storing them in impenetrable steel safes, buried treasure chests, or bank vaults.
As an added security measure you'd translate each of these documents into a secret language that only you could understand. That way, even if someone managed to break into your bank vault and steal your stuff, they wouldn't be able to understand your cryptic messages, and you'd still have lots of backups stored in other locations.
Blockchain puts this concept on steroids. Imagine you and a million friends are able to make copies of all your files, encrypt them with special software, and save them in each other's digital bank vaults (computers) all across the internet.
That way even if a hacker breaks into, steals, or destroys your computer, they can't interpret your data, and your network of friends still have 999,999 backups of your files. That's blockchain in a nutshell.