Blockchain - General Flashcards
What is Blockchain?
A decentralized ledger technology that stores data across multiple computers.
What does decentralized mean in the context of Blockchain?
It means no single entity controls the data or the network, reducing risk of manipulation.
Fill in the blank: In a blockchain, data is stored in units called ___.
Blocks.
How are blocks linked together in a blockchain?
Each block is connected to the previous block through cryptographic hashes.
What is a hash in blockchain?
A unique string of characters created from data, used to verify integrity.
Fill in the blank: Blockchain relies on a consensus mechanism to ___.
Ensure all participants agree on the state of the ledger.
What is a consensus mechanism?
A protocol used by blockchain networks to validate transactions and maintain security.
Name one popular consensus mechanism used in blockchain.
Proof of Work (PoW) or Proof of Stake (PoS).
What is Proof of Work (PoW)?
A consensus mechanism where miners solve complex puzzles to validate transactions and create new blocks.
What is Proof of Stake (PoS)?
A consensus mechanism where validators are chosen based on the number of coins they hold and are willing to ‘stake’ as collateral.
Fill in the blank: Proof of Stake (PoS) consumes ___ energy compared to Proof of Work (PoW).
Less.
What is a smart contract?
A self-executing contract with the terms of the agreement directly written into code.
Fill in the blank: Smart contracts run on the ___.
Blockchain.
How does blockchain ensure data immutability?
By using cryptographic hashing and linking blocks, making it difficult to alter any past data.
What is the primary advantage of using blockchain in supply chain management?
Transparency and traceability of products from origin to consumer.
What are nodes in a blockchain network?
Participants in the network that maintain a copy of the blockchain and validate transactions.
Fill in the blank: The distributed nature of blockchain reduces the risk of a single point of ___.
Failure.
What is the role of miners in a blockchain?
They validate transactions and add new blocks to the blockchain, typically in Proof of Work systems.
How are transactions verified in Proof of Work (PoW)?
Miners solve computational puzzles to confirm transactions and create new blocks.
What problem does blockchain solve for digital assets?
The double-spending problem, ensuring the same asset isn’t spent more than once.
Fill in the blank: A blockchain’s structure makes it highly resistant to ___.
Tampering or hacking.
What is a private blockchain?
A blockchain where access to the network is restricted to certain participants.
What is a public blockchain?
An open blockchain where anyone can join and participate.
What is a fork in blockchain?
A change to the blockchain protocol, creating a divergence in the chain.
Fill in the blank: A blockchain fork can result in two separate ___.
Chains.
What is the difference between a hard fork and a soft fork?
A hard fork creates two incompatible chains, while a soft fork remains backward-compatible.
What is Ethereum?
A decentralized, open-source blockchain that enables smart contracts and decentralized applications (dApps).
Fill in the blank: The cryptocurrency native to the Ethereum network is called ___.
Ether (ETH).
What is a smart contract on Ethereum?
A self-executing contract where the terms are written in code and run on the Ethereum blockchain.
What is the Ethereum Virtual Machine (EVM)?
A computation engine that executes smart contracts and decentralized applications on the Ethereum network.
What is the primary difference between Ethereum and Bitcoin?
Ethereum is programmable and allows for smart contracts, while Bitcoin focuses mainly on peer-to-peer transactions.
Fill in the blank: Ethereum is moving from Proof of Work (PoW) to ___.
Proof of Stake (PoS).
What is Ethereum 2.0?
An upgrade to the Ethereum network designed to improve scalability, security, and sustainability.
How does Proof of Stake (PoS) work on Ethereum?
Validators are selected based on the amount of ETH they stake, reducing energy consumption compared to Proof of Work.
What are gas fees in Ethereum?
Fees required to execute transactions and smart contracts on the Ethereum network.
Fill in the blank: Gas fees are paid in ___.
Ether (ETH).
Why are gas fees necessary in Ethereum?
To compensate network participants for the computational resources used and prevent spam on the network.
What are dApps on Ethereum?
Decentralized applications built and run on the Ethereum blockchain using smart contracts.
Fill in the blank: Ethereum is known as a platform for ___.
Decentralized finance (DeFi) and non-fungible tokens (NFTs).
What is a decentralized autonomous organization (DAO)?
An organization governed by smart contracts and run by its members without centralized leadership.
What role do DAOs play on Ethereum?
They allow decentralized decision-making and governance through smart contracts on the Ethereum blockchain.
What is ERC-20?
A technical standard for creating tokens on the Ethereum blockchain.
Fill in the blank: ERC-20 tokens are used for ___.
Creating and managing fungible tokens on Ethereum.
What is an ERC-721 token?
A token standard for creating non-fungible tokens (NFTs) on Ethereum.
How do ERC-721 tokens differ from ERC-20 tokens?
ERC-721 tokens are unique and non-fungible, while ERC-20 tokens are fungible and identical to each other.
What is a Layer 2 solution for Ethereum?
A scaling solution built on top of Ethereum to improve transaction speeds and reduce gas fees.
Fill in the blank: One popular Layer 2 solution for Ethereum is ___.
Polygon or Optimism.
What is Ethereum’s role in DeFi?
Ethereum is the primary platform for decentralized finance, enabling lending, borrowing, and trading without intermediaries.
What are smart contract vulnerabilities?
Flaws or bugs in the code of a smart contract that can be exploited by attackers.
Fill in the blank: Ethereum enables the creation of ____, which represent ownership of digital or physical assets.
Non-fungible tokens (NFTs).
What is staking in Ethereum 2.0?
Locking up ETH as collateral to help secure the network and earn rewards.
What is Bitcoin?
A decentralized digital currency that enables peer-to-peer transactions on a public blockchain network.
Who created Bitcoin?
Satoshi Nakamoto, an anonymous person or group, introduced Bitcoin in 2008.
Fill in the blank: Bitcoin transactions are verified through a process called ___.
Mining.