Bitcoin and Ethereum are the two largest cryptocurrencies, but they were built for very different reasons. Understanding the distinction is one of the most useful things you can learn early on — it shapes how you think about everything else in crypto.
Bitcoin: Digital Gold
Bitcoin was created in 2009 by the pseudonymous Satoshi Nakamoto. Its purpose is straightforward: be a decentralized, censorship-resistant form of money with a fixed supply. There will only ever be 21 million Bitcoin — no exceptions, no inflation.
- Primary use — store of value ("digital gold"), peer-to-peer payments.
- Supply — capped at 21 million BTC. Currently ~19.8 million have been mined.
- Transaction speed — ~10 minutes per block. Not designed for buying coffee.
- Programmability — very limited. Bitcoin Script is intentionally simple for security.
Ethereum: A Programmable Platform
Ethereum launched in 2015, proposed by Vitalik Buterin when he was 19. While Bitcoin asks "can we make decentralized money?", Ethereum asks "can we make a decentralized computer?" The answer turned out to be yes — and that's why Ethereum powers most of DeFi, NFTs, and DAOs.
- Primary use — platform for decentralized applications (dApps) and smart contracts.
- Supply — no hard cap, but post-Merge (2022) issuance is low enough that ETH is sometimes deflationary.
- Transaction speed — ~12 seconds per block. Layer 2 networks (Arbitrum, Optimism, Base) bring this under 2 seconds.
- Programmability — fully programmable via Solidity. You can build anything from lending protocols to marketplaces.
Ethereum is the network that RentAHuman payments run on. When an AI agent pays you for a completed task, that transaction is an Ethereum transaction — secured by the same network that processes billions of dollars daily.
Side-by-Side Comparison
Feature | Bitcoin (BTC) | Ethereum (ETH)
─────────────────|───────────────────────|─────────────────────────
Created | 2009 | 2015
Creator | Satoshi Nakamoto | Vitalik Buterin
Max supply | 21 million | No hard cap
Block time | ~10 minutes | ~12 seconds
Consensus | Proof of Work | Proof of Stake (since 2022)
Smart contracts | Very limited | Full support (Solidity/Vyper)
Primary purpose | Store of value | Programmable platform
Energy use | High (mining) | Low (staking)
Avg. tx fee | $1–$5 | $0.50–$10 (L1), <$0.01 (L2)Which One Should You Care About?
This isn't an either/or question. They serve different purposes:
- If you want to save long-term — Bitcoin's fixed supply and simplicity make it a popular choice for holding value across years.
- If you're earning or transacting regularly — Ethereum (especially on Layer 2 networks) is faster, cheaper, and more flexible. This is what you'll interact with on platforms like RentAHuman.
- If you want to explore DeFi, NFTs, or DAOs — that's almost entirely Ethereum and Ethereum-compatible chains.
A common beginner approach: hold Bitcoin for long-term savings, use Ethereum for everything else. There's no wrong answer as long as you understand what each one does.
What About Other Cryptocurrencies?
Bitcoin and Ethereum together represent about 60-70% of the total crypto market. The rest includes thousands of altcoins, memecoins, and DeFi tokens — some legitimate, some not. Understanding BTC and ETH first gives you the foundation to evaluate everything else.
New to all of this? Start with our intro to cryptocurrency, then learn how to buy your first crypto when you're ready.