Practice Test GeeksCryptocurrency Practice Test
← All Cryptocurrency Flashcard Decks

Smart Contracts and dApps Flashcards

7 cards from real Cryptocurrency practice questions. Tap to flip, then mark Knew It or Still Learning — missed cards come back until you master them.

Read the first 7 Smart Contracts and dApps flashcards as text

  1. What is a 'multisig wallet' and why is it used in dApp governance?

    Answer: A wallet that requires multiple private-key signatures to authorize a transaction, reducing single-point-of-failure risk

    Multisig wallets require M-of-N keyholders to sign before a transaction executes, making it much harder for a single compromised key to steal treasury funds or change protocol parameters.

  2. Which programming language compiles to EVM bytecode and is primarily used for Ethereum smart contracts?

    Answer: Solidity

    Solidity is the dominant high-level language for Ethereum smart contracts; it compiles to EVM bytecode and features a JavaScript-like syntax.

  3. What is 'EIP-1559' and how did it change Ethereum transaction fees?

    Answer: It split fees into a burned base fee and a priority tip, making gas costs more predictable

    EIP-1559 introduced a protocol-set base fee that is burned each block plus an optional priority tip to validators, smoothing fee volatility and making ETH deflationary under high usage.

  4. What is 'account abstraction' (ERC-4337) designed to enable?

    Answer: Smart contract wallets that can pay gas in any token, support social recovery, and bundle transactions

    ERC-4337 lets smart contracts act as user accounts, enabling features like gas payment in ERC-20 tokens, multi-call batching, and key-recovery mechanisms without protocol changes.

  5. In a DAO governed by a smart contract, what typically happens when a proposal passes?

    Answer: The smart contract automatically executes the on-chain actions defined in the proposal after a timelock

    On-chain governance contracts automatically execute approved proposals (treasury transfers, parameter changes) after a mandatory timelock period, removing the need for trusted intermediaries.

  6. What does 'TVL' (Total Value Locked) measure in DeFi?

    Answer: The aggregate USD value of assets deposited into DeFi protocols' smart contracts

    TVL is the sum of all assets held in a protocol's smart contracts at current market prices, commonly used as a benchmark for a DeFi project's adoption and liquidity depth.

  7. What is a 'token approval' and why can excessive approvals be risky?

    Answer: Permission granted to a smart contract to spend a specified (or unlimited) amount of a user's ERC-20 tokens

    ERC-20 approvals authorize a contract to transfer tokens on the user's behalf; unlimited approvals remain valid indefinitely, so a later exploit of the approved contract can drain approved balances.