Bitcoin was designed to do one thing extremely well: move value without a trusted intermediary. Ethereum asked a broader question — what if the same ledger could run arbitrary rules, not just record transfers?
That difference explains almost everything about how the two networks diverged, and it is worth understanding properly before forming a view on either.
What a smart contract actually is
The phrase is unhelpful. A smart contract is neither smart nor, in the legal sense, a contract.
It is a program stored on the blockchain that executes exactly as written when its conditions are met. Nobody can stop it, nobody can alter it after deployment, and nobody decides whether to honour it. There is no discretion anywhere in the system.
A useful comparison: a vending machine. You insert payment, the machine dispenses. It does not evaluate whether you deserve the product, it does not have a bad day, and it cannot be persuaded. A smart contract is that logic applied to money, ownership and permissions.
The power and the danger are the same property. Code that executes exactly as written executes bugs exactly as written too. There is no appeals process, and hundreds of millions of dollars have been lost to contracts that did precisely what their code said rather than what their authors intended.
Gas, and why it exists
If anyone can deploy a program that every node must run, what stops someone deploying an infinite loop and halting the network?
Gas. Every operation costs a small amount, paid in ETH. Complex operations cost more. An infinite loop simply runs until it exhausts the gas supplied and then stops.
That is why ETH is required to use the network. It is not primarily a currency in the Bitcoin sense — it is the fuel that makes computation on a shared machine economically bounded. This is the single most important mechanism to understand about Ethereum, and it is usually skipped.
Gas prices rise with demand. When the network is congested, the same transaction costs considerably more, because users effectively bid for inclusion. This is why fees can vary from cents to tens of dollars for identical operations, and it is a market outcome rather than a malfunction.
The move to proof of stake
Ethereum originally used proof of work, the same energy-intensive mechanism Bitcoin uses. It moved to proof of stake, cutting energy consumption by roughly 99%.
Under proof of stake, validators lock up ETH as a bond. They are selected to propose and attest to blocks, and dishonest behaviour causes the protocol to destroy part of that bond — a process called slashing. Security comes from having capital at risk rather than energy consumed.
The honest trade-off, which advocates tend to skip: influence tracks capital, and the long-term behaviour of proof of stake under severe adversarial conditions is less battle-tested than proof of work's decade-plus record. Both mechanisms have real strengths. Anyone telling you one is simply superior is not describing the engineering.
Layer 2: where the activity actually happens now
Ethereum's base layer is deliberately conservative. It prioritises security and decentralisation over throughput, which means it cannot process enough transactions for global use at acceptable cost.
The answer was not to make the base layer faster. It was to move execution elsewhere and use Ethereum for settlement.
Layer 2 networks — Arbitrum, Optimism, Base and others — process transactions off the main chain, then post compressed proofs back to it. You get dramatically lower fees while inheriting Ethereum's security guarantees for final settlement.
This is the part most explanations get wrong. If you use Ethereum applications today, you are probably transacting on a Layer 2 rather than on Ethereum itself. The base layer has become settlement infrastructure — closer to what a clearing house does than to a payment network.
The practical consequence for anyone using it: you must know which network your funds are on. Sending assets to the right address on the wrong network is a common and often unrecoverable mistake.
What gets built on it
Stablecoins. By far the largest real use. Dollar-denominated tokens moving on Ethereum and its Layer 2s settle enormous volumes, and this is the clearest product-market fit the network has.
Decentralised finance. Lending, borrowing and exchange without an intermediary deciding who qualifies. Genuinely novel, and genuinely risky — these are programs holding money, and programs have bugs.
Tokenisation. Representing ownership of things on a ledger. This has moved from theory to practice: the SEC issued a conditional exemption in September 2026 allowing tokenised US equities to trade on permissioned automated market makers, and the ECB has begun buying tokenised public-sector securities through its Pontes platform.
NFTs. After the speculative collapse, the durable uses are narrower than promised — ticketing, credentials, provenance — but they have not disappeared.
Ethereum and Bitcoin are not competitors
They are optimised for different things, and the "which is better" framing produces bad thinking.
Bitcoin optimises for being unchangeable, predictable and maximally secure. Its conservatism is the product. A fixed supply schedule and a protocol that resists change is exactly what a store of value needs.
Ethereum optimises for capability and adapts. It has changed its consensus mechanism, restructured its scaling approach and altered its fee model. That flexibility is what lets it host applications, and it is also a different risk profile — a system that can change is a system that can change in ways you did not want.
Holding a view that one must win requires believing the two are solving the same problem. They are not.
Staking, and what it actually involves
Because ETH secures the network, holders can earn rewards by staking it. This is widely misunderstood as an interest rate. It is not.
Rewards come from new issuance and transaction fees, paid for performing a job — validating the chain. Fail at that job, or attempt to cheat, and slashing destroys part of your stake. Running a validator independently requires 32 ETH and genuine operational responsibility, including uptime.
Pooled and liquid staking services lower the barrier, and they introduce their own risks: smart contract risk in the pooling contract, counterparty risk with the operator, and the concentration risk of a small number of providers controlling a large share of validation.
Anyone presenting staking yield as a risk-free return has omitted the entire risk section.
Tax and regulation, by region
US: disposals are reportable capital events, and broker reporting is expanding under Form 1099-DA. Staking reward taxation has been contested; take advice rather than assuming.
UK: HMRC treats most disposals as capital gains, with staking rewards generally treated as income on receipt.
EU: MiCA governs service providers. Tokenised securities fall under MiFID rather than MiCA, since MiCA does not cover securities.
India: gains taxed at 30% with 1% TDS on transfers; maintain independent records regardless of exchange statements.
How to evaluate anything built on Ethereum
One question cuts through most of it: who are the parties here that do not trust each other?
If there is no clear answer, the application does not need a blockchain, and using one makes it slower, more expensive and more fragile than a conventional database would be. A very large share of what was built between 2020 and 2023 failed this test, which is why so little of it survives.
Two follow-ups worth asking: has the contract been audited, and by whom? And what happens if the team disappears — does the application keep working, or does it depend on a company staying alive?
The honest summary
Ethereum is a shared computer that anyone can deploy programs to, where the programs cannot be stopped or altered and everyone can verify what they do. That is genuinely new, and the stablecoin and tokenisation use cases demonstrate real demand rather than speculation.
It is also slow and expensive compared with a database, unforgiving of bugs, and surrounded by a great deal of activity that does not need it at all. Both of those things are true simultaneously, and holding both is the difference between understanding this technology and merely having an opinion about it.
This article is educational and is not investment advice. It contains no price predictions. Crypto assets are volatile and you can lose money. Do your own research and speak to a regulated adviser in your jurisdiction.