Blockchain: Definition?

Blockchain: Definition?

• A. A digital ledger in which transactions made in bitcoin or another cryptocurrency are recorded chronologically and publicly.
• B. A social media platform.
• C. A private file storage system.
• D. A search engine.

Answer: (A)

The key idea is that blockchain is a distributed digital ledger that records cryptocurrency transactions across many computers, in a way that is chronological and publicly verifiable. Each block groups a set of transactions and is linked to the previous one, forming an immutable chain. Because the ledger is maintained across a network of nodes rather than by a single central authority, it remains transparent and resistant to tampering; altering past records would require consensus across the network. This makes the description of a digital ledger recording cryptocurrency transactions in a public, chronological manner the best fit. The other options describe entirely different technologies: a social media platform is about sharing content online, private file storage is centralized and private, and a search engine focuses on indexing and retrieving information, not maintaining a distributed, tamper-resistant ledger of transactions.

The key idea is that blockchain is a distributed digital ledger that records cryptocurrency transactions across many computers, in a way that is chronological and publicly verifiable. Each block groups a set of transactions and is linked to the previous one, forming an immutable chain. Because the ledger is maintained across a network of nodes rather than by a single central authority, it remains transparent and resistant to tampering; altering past records would require consensus across the network. This makes the description of a digital ledger recording cryptocurrency transactions in a public, chronological manner the best fit. The other options describe entirely different technologies: a social media platform is about sharing content online, private file storage is centralized and private, and a search engine focuses on indexing and retrieving information, not maintaining a distributed, tamper-resistant ledger of transactions.