IGCSE 0478 CompSci - Digital Currency

What is the primary characteristic of Bitcoin as a currency?

• It is issued by a central government

• It requires banks to manage accounts

• It is a fully digital currency

• Its inventor is widely known

What is the main purpose of the communal ledger described in the introduction?

• To keep track of physical cash exchanges

• To record intended future payments

• To store cryptocurrency mining data

• To verify bank transactions

How often do participants settle up in the initial ledger system described?

• Daily

• Weekly

• Monthly

• Yearly

What cryptographic concept is introduced to prevent unauthorized transactions?

• Blockchain

• Digital signatures

• Hash functions

• Public ledgers

What does a digital signature depend on?

• The message and the sender's private key

• Only the sender's public key

• The recipient's private key

• The time of the transaction

How many bits are typically used in a digital signature?

• 64 bits

• 128 bits

• 256 bits

• 512 bits

What is the purpose of including a unique ID with each transaction?

• To speed up transaction processing

• To reduce the ledger size

• To prevent copying of transactions

• To identify the transaction recipient

In the ledger system, what does 'LD' stand for?

• Legal Deposit

• Ledger Dollars

• Limited Distribution

• Liquid Debit

What fundamental concept about cryptocurrency is emphasized in the video?

• The ledger is the currency itself

• Cryptocurrencies are backed by gold

• Banks control all cryptocurrencies

• Cryptocurrencies are only for illegal activities

How do new ledger dollars enter the system in the initial example?

• Through mining

• By government issuance

• By participants buying in with cash

• Through bank loans