Blockchain is a distributed, append-only digital ledger that records transactions across many computers so that records cannot be altered retroactively without changing all subsequent blocks.
It removes the need for a central trusted authority by using cryptography and a network consensus mechanism, making it the backbone of cryptocurrencies and many enterprise data-integrity systems.
Data is grouped into blocks. Each block stores a list of transactions, a timestamp, and a cryptographic hash of the previous block. This chaining of hashes is what makes the chain tamper-evident: altering one block changes its hash and breaks the link to every block after it.
New blocks are validated by network nodes using a consensus algorithm such as Proof of Work (used by Bitcoin) or Proof of Stake (used by modern Ethereum). Once the majority agrees, the block is added permanently and broadcast to all participants.
Smart contracts are self-executing programs stored on the blockchain that run automatically when predefined conditions are met. They enable decentralized applications (DApps), removing intermediaries in areas such as finance, insurance, and supply chain.
| Aspect | Details |
|---|---|
| Branch | Computer Science Engineering (CSE) |
| Topic Type | Technical Seminar / Project Report |
| Difficulty | Intermediate – Advanced |
| Best For | Final-year BTech seminars & presentations |
| Includes | Explanation, key points, FAQs & references |