Dive deep into the realm of Ethereum with our compilation of Top 30+ Ethereum Interview Questions. Gain a solid understanding of Ethereum, its underlying technology, and the essential concepts that drive the blockchain platform. Check out this complete list of interview questions and their well-thought-out answers, written to help you do well in Ethereum-related job interviews.
Ethereum has become one of the most talked about technologies in the world of blockchain and cryptocurrency. As interest and adoption of Ethereum grows, so does the need for developers and professionals with knowledge of how the platform works.
In this complete guide, I’ll be covering some of the most common and important Ethereum interview questions that you’re likely to encounter when applying for roles related to Ethereum, smart contracts, and blockchain development.
Whether you’re the interviewer looking to test a candidate’s skills, or the interviewee wanting to be fully prepared, this guide aims to provide you with all the details needed to ace an Ethereum interview.
What Exactly is Ethereum?
Ethereum is an open-source decentralized blockchain platform that runs smart contracts. It’s kind of like Bitcoin but expanded functionality to allow developers to build and deploy decentralized applications (dApps).
The Ethereum network has its own native cryptocurrency called Ether (ETH) which is used to pay for transaction fees and computational services on the network.
Who Created Ethereum and When?
Ethereum was first proposed in 2013 by Vitalik Buterin and officially launched in 2015. Buterin wrote the initial white paper outlining the vision and technology behind Ethereum.
Along with other co-founders like Gavin Wood, Jeffrey Wilcke, and Charles Hoskinson, Buterin engineered and designed the first implementations and continued to contribute to improving Ethereum in various ways.
What is the Ethereum Virtual Machine (EVM)?
The Ethereum Virtual Machine (EVM) is the runtime environment for smart contracts in Ethereum. It provides a standardized execution environment so that smart contracts can be run exactly as programmed without variation.
The EVM executes a contract’s bytecode on a global network of public nodes. It isolates code execution from the main network to allow execution without real-world interference.
What is Ether and How is it Used?
Ether (ETH) is the native cryptocurrency of the Ethereum network. It acts as ‘gas’ that powers the execution of transactions and smart contracts.
Ether is used to pay transaction fees to get your transaction processed faster by miners. It’s also used to deploy and run smart contracts on Ethereum.
What is Gas in Ethereum?
In Ethereum, gas refers to the unit that measures the computational effort required to execute specific operations on the Ethereum network.
Since computation takes real-world resources, gas aims to mitigate resource wastage on the network. It provides a pricing mechanism for resources used while preventing network abuse. The more complex the execution, the more gas required.
Gas price is specified in Ether. You pay for the computation proportional to the resources (gas) consumed. Unused gas is refunded.
What is a Smart Contract?
A smart contract is a self-executing program that runs on the Ethereum blockchain. It is written as code that defines the terms of the agreement, which is implemented programmatically.
Smart contracts allow the performance of credible transactions without centralized authorities and enforcement costs. Once deployed on the blockchain, smart contracts are immutable and automatically execute when predetermined terms and conditions are met.
How Does Mining Work in Ethereum?
Ethereum currently uses a Proof-of-Work consensus mechanism for mining new blocks. Miners compete to solve computationally intensive cryptographic puzzles in order to validate transactions and create new blocks.
Solving the puzzle first gives the miner exclusive right to add the new block to the blockchain and earn Ether as a reward for the efforts along with gas fees for processing transactions in the block.
What is the Difference Between Ethereum and Bitcoin?
While both Ethereum and Bitcoin are decentralized cryptocurrencies, there are some key differences:
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Bitcoin is primarily designed as a digital currency for payments while Ethereum is more of a platform to run decentralized applications using smart contracts.
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Ethereum offers a broader scripting language whereas Bitcoin has limited scripting capability.
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Ethereum uses the EVM for running smart contracts while Bitcoin does not have an equivalent.
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Ethereum plans to eventually move to Proof-of-Stake while Bitcoin continues to use Proof-of-Work.
What is Solidity and Why is it Used?
Solidity is a contract-oriented high-level programming language used for writing smart contracts on Ethereum. It is statically-typed and similar to Javascript.
Solidity gets compiled into bytecode that runs on the EVM. Using Solidity allows developers to write human-readable code that implement transaction logic for smart contracts.
How Can You Deploy a Smart Contract?
There are a few ways to deploy smart contracts on Ethereum:
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Using online IDEs like Remix which provide an environment to write, deploy, and administer contracts.
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Writing and compiling smart contract code locally then using various APIs like web3.js or Ethers.js to deploy the bytecode to the network.
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Using deployment tools like Truffle that automate contract compilations, deployments, testing etc.
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Writing custom deployment scripts that suit specific requirements.
What is a DApp? How is it Different From Normal Apps?
A DApp or decentralized application contains backend code that runs on a decentralized peer-to-peer network like Ethereum. Normal apps have backend code running on centralized servers.
In normal apps, the backend code is controlled by a central authority. But in a DApp, smart contracts replace the backend code. These smart contracts are deployed on the blockchain and are immutable.
The frontend can be traditional web or mobile apps that interact with the smart contracts through APIs.
What are Some Popular DApps Based on Ethereum?
Some popular Ethereum-based DApps across sectors like finance, games, collectibles, identity, governance etc are:
- Maker – Stablecoin and lending platform
- Uniswap – Decentralized crypto exchange
- CryptoKitties – Collectible non-fungible tokens
- Aragon – Decentralized governance platform
- Uport – Self-sovereign identity
- Gitcoin – Decentralized open-source funding
How Can DApps Scale for Mass Adoption?
Some potential solutions for Ethereum scaling to support higher transaction volumes for mass DApp adoption are:
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Sharding – Splitting network nodes into smaller groups or shards that process transactions parallelly.
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State Channels – Moving transactions and computation off-chain while leveraging blockchain for enforcing contract agreements.
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Plasma – Using hierarchical side-chains anchored to the main Ethereum blockchain periodically.
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Truebit – Offloading intensive computations off-chain.
What are Some Ways to Interact With Ethereum?
There are various ways to interact with the Ethereum blockchain:
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With Ethereum clients like Geth and Parity that connect to the network for querying state, making transactions etc.
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Using Web3.js library to interact with Ethereum nodes from JavaScript apps.
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Through explorer websites like Etherscan for viewing transaction details, balances etc.
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Via various APIs provided by services like Infura, Alchemy etc to fetch data and push transactions.
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With Ethereum wallets like MetaMask, MyEtherWallet etc for managing keys and transacting.
What are Some Trends in Ethereum to Look Forward to?
Some trends shaping Ethereum’s future are:
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Transition to proof-of-stake consensus through the Ethereum 2.0 upgrade for improved security, scalability and sustainability.
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Adoption of layer-2 scaling solutions like rollups and state channels to support DApp growth.
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Growing use of stablecoins and decentralized finance applications.
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Increased integration of oracles and real-world data into smart contracts.
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Gradual institutional investment and regulation around Ethereum.
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Enabling private and confidential transactions through advances in cryptography.
With these Ethereum interview questions, you should now have a broad understanding of Ethereum’s fundamental concepts from its origins and purpose to smart contracts, mining, scalability, and future trends.
Whether you are learning about Ethereum for the first time or brushing up on concepts as an experienced practitioner, this guide equips you with sufficient knowledge to tackle common Ethereum interview questions confidently.
The list covers a diverse range of questions from basics and working concepts to applications and future outlook. With blockchain technology adoption accelerating, knowledge of Ethereum will be an invaluable asset for any developer or professional in the space.
Explain the concept of a Merkle Tree in Ethereum.
A Merkle Tree is a type of data structure that is used in Ethereum and other Blockchain systems to keep track of transactions in a block and make sure they are valid. It is named after its inventor, Ralph Merkle. In Ethereum, Merkle Trees play a pivotal role in providing the safety and transparency of the Blockchain.
Here is how a Merkle Tree works:
a) Transaction organisation: In each Ethereum block, multiple transactions are bundled together. To create a Merkle Tree, these transactions are organised into pairs.
A cryptographic hash function, usually SHA-256, is used to hash the data of each pair, creating a unique hash value for each team. They are then put together again and hashed until there is only one soup left, called the Merkle Root.
c) Merkle root: The Merkle Root is a single hash value representing all the block transactions. It is included in the blocks header, making it a fundamental part of its identity.
d) Verification: A node in the Ethereum network only needs to know the Merkle Root and the position of a transaction in the league to verify a certain transaction within a block. Through the hash path from the transaction to the Merkle Root, the node can quickly confirm that the transaction is included without having to go through each transaction in the block.
What is Ethereum?
Ethereum is a revolutionary Blockchain-based platform that has transformed the world of decentralised technology and digital finance. Ethereum is a decentralized and open-source ecosystem that was started by Vitalik Buterin in 2014. It lets developers make a wide range of apps and Smart Contracts, all of which are controlled by a safe and open network.
Ethereum is more than just a cryptocurrency; it’s a decentralized computer that runs code and makes it easier to make Decentralized Applications (DApps). Bitcoin’s main purpose is to be a digital currency. Ethereum’s main purpose is to be a place where new ideas can be tested.
One of the most innovative things about Ethereum is its smart contracts, which are agreements between two parties that automatically carry out and make sure they can be trusted without the need for a third party.
Interview Question | What Is Ethereum Transaction Or Data Structure
FAQ
What are the biggest risks to Ethereum?
What is Ethereum everything you need to know?
What makes Ethereum special?
What are the challenges of Ethereum?
How do you answer Ethereum interview questions?
You can answer such basic Ethereum interview questions by highlighting network congestion, maintenance, and performance overheads. In addition, the development of user-friendly interfaces and experiences, alongside avoiding the possibilities of centralization, also affects app development. 11.
How to answer Ethereum & smart contracts interview questions?
You can answer such Ethereum & smart contracts interview questions by referring to recommended steps in verification. The first step involves the input of source files and compilation settings in a compiler which generates the contract bytecode. You must now obtain the contract’s bytecode deployed at the concerned address.
What is the goal of Ethereum?
Ethereum aspires to expand the use of blockchain technology via the use of intelligent contracts. Hence, decentralized apps and smart contracts can develop and operate without interruption, fraud, or outside influence on the Ethereum platform.
What skills are required for Ethereum development?
Ethereum developers need various skills to work effectively. They must understand Ethereum development, including smart contracts, transactions, consensus algorithms, sharding, and token standards.
