Core Concepts Flashcards
7 cards from real Blockchain Technology practice questions. Tap to flip, then mark Knew It or Still Learning — missed cards come back until you master them.
Read the first 7 Core Concepts flashcards as text
What is the UTXO model used in Bitcoin, and how does it differ from the account model used in Ethereum?
Answer: UTXO tracks unspent transaction outputs; account model tracks balances directly in named accounts
Bitcoin's UTXO model tracks individual unspent outputs as spendable inputs, while Ethereum's account model maintains a global state of balances.
What is 'block propagation' and why does its speed matter in blockchain networks?
Answer: The time it takes for a newly mined block to reach all nodes, affecting orphan block rates
Slow block propagation increases the chance of competing miners producing orphan blocks simultaneously, wasting computational resources.
What role does a blockchain explorer serve for end users?
Answer: It provides a searchable interface to view transactions, blocks, and wallet addresses on the blockchain
Blockchain explorers like Etherscan or Blockchain.info let users look up transaction status, wallet balances, and block details in real time.
What is a multi-signature (multisig) transaction and what security benefit does it provide?
Answer: A transaction that requires multiple private key signatures before it can be executed
Multisig requires M-of-N designated private keys to sign a transaction, reducing single-point-of-failure risk.
In Proof of Stake, what is 'slashing' and why is it important?
Answer: Penalizing validators who act maliciously by destroying part of their staked tokens
Slashing deters dishonest validator behavior (e.g., double-signing) by burning a portion of their staked collateral as punishment.
What is an 'orphan block' (also called a stale block) in blockchain?
Answer: A valid block that is not included in the main chain because another block at the same height was accepted first
Orphan blocks occur when two miners solve a block simultaneously; only one is adopted into the longest chain, making the other orphaned.
What cryptographic primitive allows a user to prove ownership of a private key without revealing it during a blockchain transaction?
Answer: Digital signature (e.g., ECDSA)
Digital signatures like ECDSA let a user sign a transaction with their private key; anyone can verify it with the corresponding public key without learning the private key.