Blockchain Review

a blockchain is?

• is a digital ledger.

• makes Bitcoin and other cryptocurrencies possible.

• can make transactions recorded chronologically and public.

• all of the above.

As stated in the video, cryptography is the practice of encoding information so that only authorized people can read it.

• True

• False

In the video, hashing is described as one of the types of Cryptography that we can use to secure data and is not the foundation of blockchains.

• True

• False

a blockchain is a distributed database that uses a large network of computing devices.

• True

• False

What year was blockchain invented?

• 2011

• 2020

• 2008

• 2023

What is an example of a company that uses blockchain? (Select all that apply)

• Bitcoin

• Coinbase

• Ethereum

• Amazon

Transactions that are made using cryptocurrency are verified before they can be added to the ledger.

• True

• False

Why is blockchain important?

• Helps companies create a transparent environment for their customers.

• Creates a faster and more secure way to protect information.

• Both A and B.

• Neither A nor B.

Proof of work

• 1. is what blockchain technology is based on.

  
  

• 1. allows people to get paid some kind of cryptocurrency on a blockchain.

  
  

• allows people to PROVE they have worked on the blockchain through a transaction of some kind.

• All of the above.

Hashing in a blockchain

• 1. changes a transaction into an unreadable string of text for the purpose of encrypting the transaction.

  
  

• takes input data of arbitrary length and produces a fixed-size (always the same size) output.

• is generated by a mathematical formula inside of a computer program so that it is REALLY unlikely that some other transaction will produce the same hash value.

• All of the above.