Blockchain typically refers to the transparent, trustless, publicly accessible ledger that allows you to securely transfer the ownership of units of value using public-key encryption and consensus methods.

The first successful implementation of Blockchain technology is Bitcoin. The potential of Blockchain is not limited to Bitcoin only. It has gained popularity among various industries, including financial services, charities and nonprofits, the arts, and e-commerce.

Marco and Lakhani define Blockchain as "An Open, Distributed ledger that records the transactions between two parties in an efficient manner and in a Verifiable and Permanent way,” they mentioned in Harvard Business Review.

If you look at the above definition carefully, you can observe keywords like:

• Open (Accessible to all)
• Distributed or Decentralized (No single party control)
• Verifiable (Everyone can validate the information)
• Permanent (The info is persistent)

The keywords mentioned above are significant to understand Blockchain better. The keyword Open refers to the access control of the Blockchain. It is accessible by all the users of the Blockchain network. 

Distributed or Decentralized keyword refers to the control access of the users of the Blockchain. The data in a Blockchain is distributed among all the users. No single user is the central authority, and all of them have significant control over the Blockchain.

In Blockchain, every user can verify the transactions and blocks. The Verifiable feature refers to the validity checking. The Permanent feature keyword refers to the life span of the information stored in Blockchain. It is a persistent storage structure.

Blockchain technology underlies cryptocurrency networks, and it is used in a wide variety of other applications. Blockchain networks combine private key technology, distributed networks, and shared ledgers. Confirmation and validation of the transactions are the crucial functions of the Blockchain for a cryptocurrency.

Suppose you consider the traditional way of sharing the documents between two parties where it is a centralized system, and each party can’t modify the data at a time. In this scenario, if data gets affected by any vulnerabilities or system failure, the data will not be available to any of the parties. Hence, there is more chance of data and integrity loss in this system.

Taking the example of the Google document between two parties, a centralized one, users can modify the document at a time. If this system faces any vulnerabilities or any system crash, then it may result in data loss.

For all these problems, Blockchain provides the solution. In Blockchain, every user can edit the data on their local copy of the document. The internet ensures consistency and updates. Blockchain is also known as an internet database. It is a decentralized system, where a central unit takes care of all the data and transactions.

The core component of Blockchain is a block. Blocks store information regarding transactions, the number of participants, and the ID of that block separates it from the rest of the blocks in the Blockchain.

The Blockchain node collects the transaction details over a certain period and mines a block. The block constructed is then verified and validated by the validator nodes in the network. Based on the consensus mechanism, the block is added to the Blockchain.  

Blockchain is a distributed system in which a local copy of the global data will be maintained at every node. Each of these local copies gets updated based on the global data. These local copies are nothing but the public ledger. The system ensures consistency among all the documents of data in the network.

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