Compare it to a public ledger
Although blockchain may seem complex, its core concept is actually quite simple. Blockchains serve as a form of a database. First, we need to explain what a database is in order to understand blockchain.

Database
/ˈdeɪtəbeɪs/
Noun
a structured set of data held in a computer, especially one that is accessible in various ways.
“A database covering the numbers of citizens the house watches over “
Databases are collections of information that are stored electronically in a computer system. Information, or data, in databases is typically structured in table format to allow for easier searching and filtering for specific information. When someone uses a spreadsheet to store information, how is that different from using a database?
A spreadsheet is designed for storing and sharing small amounts of information among a few people. The database, on the other hand, is designed to hold much larger volumes of information that can be accessed, filtered, and manipulated by any number of users simultaneously.
A large database achieves this by housing data on servers that are comprised of powerful computers. Many of these servers can sometimes be built utilizing hundreds or thousands of computers in order to provide the processing power and storage capacity that allows many users to access the database at the same time. Despite the fact that a spreadsheet or database can be accessed by any number of people, it is typically owned by a business and managed by an individual who has complete control over how it works and how the data is stored.