Blockchain : Practice Questions and Answers

Blockchain is a decentralized ledger technology where transactions are recorded in a secure, immutable way. It eliminates the need for intermediaries and ensures transparency and security across the distributed network.

The Genesis Block is the very first block in a blockchain, forming the foundation upon which all subsequent blocks are added.

Satoshi Nakamoto introduced blockchain technology in 2008 as the foundation for Bitcoin, the first cryptocurrency.

Immutability ensures that once data is added to the blockchain, it cannot be altered, making the system tamper-resistant.

Bitcoin, introduced in 2009, was the first cryptocurrency to leverage blockchain technology for secure and decentralized transactions.

Blockchain is primarily designed to securely and transparently record transactions, ensuring data integrity and reducing the need for intermediaries.

Blockchain is a decentralized ledger that stores data across a distributed network, ensuring security and transparency.

A blockchain consists of multiple blocks, each containing transaction data, a timestamp, and a reference to the previous block.

Decentralization reduces security risks by eliminating a single point of failure and ensuring data is distributed across a network of nodes.

A distributed ledger refers to a database that is spread across multiple nodes in a network, ensuring transparency and security.

A blockchain ledger can store various types of verified data, including financial transactions, supply chain records, and digital identities.

A block is the fundamental unit of a blockchain that contains a group of transactions, a timestamp, a hash of the previous block, and a unique identifier (hash).

A Merkle tree is a data structure that organizes transactions in a block into a tree-like structure. It allows efficient verification of transaction data integrity by checking hashes.

Cryptographic hashing ensures data immutability by generating a unique hash for each block. Any modification to the block changes its hash, making tampering evident.

A full node stores a complete copy of the blockchain and participates in validating and relaying transactions across the network.

Blockchain operates on a peer-to-peer network where all nodes share and verify information without a central authority, ensuring decentralization.

A consensus algorithm ensures all nodes agree on the validity of transactions and the state of the blockchain, maintaining consistency and security in a decentralized network.

Miners validate transactions and add them to the blockchain by solving complex computational problems. This process also helps secure the network.

A cryptocurrency is a digital or virtual currency that uses cryptographic techniques to secure transactions, control the creation of new units, and verify asset transfers.

Mining is the process of validating transactions and adding them to the blockchain while creating new Bitcoin as a reward for solving complex computational puzzles.