What Is Ethereum? A Beginner's Guide to ETH

Ethereum is a decentralized, programmable blockchain that runs smart contracts — self-executing code — using its native cryptocurrency, ETH, to pay for computation and transactions, distinguishing it from Bitcoin, which is primarily designed as a monetary network.

Launched in 2015, Ethereum extended the blockchain concept pioneered by Bitcoin beyond simple value transfer into a general-purpose computing platform. Where Bitcoin's scripting language is deliberately limited, Ethereum was built so developers could write arbitrary programs that run on a decentralized network of computers. For a comparison of Bitcoin's design, see what Bitcoin is.

ETH the asset vs Ethereum the platform

It helps to separate two things people mean when they say "Ethereum":

• ETH: The native cryptocurrency of the network. It's used to pay transaction fees (called "gas"), and can be transferred, held, or used within decentralized applications.
• Ethereum: The underlying blockchain and its execution environment, which processes smart contracts and hosts thousands of applications ranging from financial tools to games to digital collectibles.

This distinction matters because Ethereum's value proposition isn't just "digital money" — it's a platform other applications are built on top of, similar to how an operating system hosts many different apps.

Smart contracts: the core innovation

A smart contract is code deployed to the blockchain that executes automatically when its conditions are met, without needing a trusted intermediary to enforce the terms. Once deployed, a smart contract's logic runs exactly as written and cannot be altered by any single party. Our deeper explainer on what a smart contract is walks through this with a simple analogy.

Smart contracts underpin nearly everything built on Ethereum:

• Decentralized finance (DeFi): Lending, borrowing, and trading protocols that operate without a bank or brokerage. See our overview of what DeFi is.
• Stablecoins: Digital tokens designed to track a stable value, often the US dollar, explained in our stablecoins guide.
• NFTs: Unique digital tokens representing ownership of an item, covered in our NFT explainer.
• Decentralized exchanges: Trading platforms without a central operator, compared to centralized alternatives in our DEX vs CEX guide.

How Ethereum processes transactions

Every action on Ethereum — sending ETH, interacting with a smart contract, minting an NFT — is executed inside the Ethereum Virtual Machine, a standardized runtime that every node on the network runs identically. Our explainer on what the EVM is covers this in detail. Because every node re-executes the same computation and reaches the same result, the network stays in consensus about the current state of every account and contract.

Ethereum vs Bitcoin at a glance

Feature	Bitcoin	Ethereum
Primary purpose	Store of value, peer-to-peer payments	Programmable platform for applications
Scripting capability	Limited, intentionally restricted	Full smart contract programmability
Consensus mechanism	Proof of work	Proof of stake (since the 2022 Merge)
Native asset	BTC	ETH
Typical use cases	Holding, payments	DeFi, NFTs, tokenization, dApps

Our proof of work vs proof of stake guide and layer 1 blockchain comparison go further into how these consensus and design choices play out across different networks.

Fees and scaling

Using Ethereum requires paying gas fees, priced in ETH, which can rise significantly when network demand is high. This has driven the growth of layer 2 networks that process transactions more cheaply while still settling back to Ethereum for security — see our gas fees explainer and layer 2 guide for more.

Risks to understand before getting involved

Ethereum and its applications carry real risks: smart contracts can contain bugs or be exploited, token prices are volatile, and interacting with unfamiliar protocols can expose funds to scams. Our common DeFi scams guide and wallet security guide cover practical precautions. Tax obligations also apply in most jurisdictions when trading or earning crypto — see our crypto taxes guide.

Bottom line

Ethereum is best understood as a global, shared computer that anyone can build on, with ETH as the fuel that powers it. Its value comes not from being "just money" but from the applications — DeFi, stablecoins, NFTs, and more — that smart contracts make possible on top of it.