This lesson on Blockchain Basics & Consensus explains how blockchain systems operate and how they achieve agreement across decentralized networks without a central authority. It is a key concept for understanding how trust is maintained in distributed systems.

The lesson begins with the basics of blockchain, describing it as a chain of blocks that store data in a secure and transparent way. Each block contains transaction data, a timestamp, and a cryptographic link to the previous block, forming an immutable ledger.

It then introduces the concept of consensus mechanisms, which are the rules that allow all participants in the network to agree on the state of the blockchain. Without consensus, there would be no way to ensure that all nodes share the same version of data.

Common consensus models such as Proof of Work and Proof of Stake are used to validate transactions and add new blocks to the chain. These systems ensure security, prevent fraud, and maintain the integrity of the network.

By the end of this lesson, learners will understand how blockchain structures data and how consensus algorithms keep decentralized systems