Smart Contracts 101

What parameter is used to find a Smart Contract in Ethereum?

• Locator

• ABI

• DID

• Address

Answer explanation

The Ethereum blockchain uses addresses to locate wallets and deployed smart contracts

What is sent to the Ethereum blockchain to execute an arbitrary transaction?

• GLO

• Transaction Payload

• ABI

• Bytecode

Answer explanation

The Ethereum blockchain only understands an specific transaction payload. GLOs, for example, are a concept of Marco and not of a particular blockchain. The bytecode is the specific name for compiled smart contracts on Ethereum.

Are all smart contracts trustless?

• Yes

• They can be as long as the blockchain is trustless

• Depends on how it is programmed and managed

• No

Answer explanation

They are not all trustless, they can be made so that dynamic behaviours can be set in. They can also be modified without user consent on some blockchains.

What is an advantage of Smart Contracts over traditional apps?

• More capacity for trustlessness

• They are faster

• They are simpler to code

• They are trendy

Answer explanation

Trustlessness is the real beenfit of using an smart contract

What is a common saying in the Blockchain lingo?

• Code is right

• Coleslaw

• Code is law

• Satoshi is reptilian

Can smart contracts be hacked?

• No, it is trustless

• Yes, there can be bugs

• No, code is law

• Yes, you can the node

Answer explanation

If there is a bug in a smart contract caused by the developer, there's nothing the ledger can do about that

What is the interface object that is used to communicate with an Ethereum Smart Contracts natively?

• OpenAPI

• Address

• ABI

• Wallet Plugin

Answer explanation

The ABI is a representation of the interface of a Smart Contract. It is similar to an OpenAPI but with more information to the Ethereum domain.

Do you need a wallet to send transactions to Ethereum?

• No, you can modify the state of a contract without one

• No, you can read the state without problems

• Yes, all transactions need to be signed

Answer explanation

Transactions modify the state of Ethereum, so you do need to sign a transaction. To sign a transaction you need a wallet.

What is a common misconception of Smart Contracts? Regardless of ledger technology

• Source code is immutable

• Code is law

• Ferreiro Joefers are ledger generic

Answer explanation

Smart contracts on Ethereum are immutable, but for some blockchains like Hyperledger Fabric and ICP that is not the case.

What is a common misconception of blockchains? Regardless of ledger technology

• Transactions are read operations

• Transactions are executed by the blockchain

• Transactions are always final

Answer explanation

Transactions may not always be final. In some cases it can be rollbacked.