3. Bitcoin vs Ethereum vs Altcoins
HODL Guide Pro · Crypto 101
Module 3 of 12
Module 3 of 12
Bitcoin vs Ethereum vs Altcoins
There are thousands of coins. You only need to understand a few categories to make sense of all of them — and to spot the risky ones.
The main categories
| Type | What it is | Think of it as |
|---|---|---|
| Bitcoin (BTC) | The original crypto; fixed, scarce supply | Digital gold / store of value |
| Ethereum (ETH) | A platform that runs smart contracts | A world computer for apps |
| Stablecoins | Coins pegged to a currency (e.g. the US dollar) | Digital cash for moving value |
| Altcoins | Thousands of other projects, wildly varying quality | Everything from serious to scam |
Altcoin reality check
Most altcoins fail. Before touching one, ask: who’s behind it, what problem does it solve, is the team public, and is there real usage — or just hype? If you can’t answer, that’s your answer. (Educational, not investment advice.)
What a smart contract does
A smart contract is code that runs exactly as written when conditions are met — no middleman needed. “If X happens, automatically do Y.” It powers DeFi, NFTs, and more (Modules 10 and 11), but code can have bugs, so it carries its own risks.
Key takeaways
- Bitcoin = scarce store of value; Ethereum = programmable platform.
- Stablecoins aim for a steady price and are handy for payments.
- Most altcoins are high-risk — scrutinize before trusting.
Educational purposes only — not financial, investment, or tax advice. Crypto is volatile; rules vary by country and change often. HODL Guide never asks for your seed phrase or private keys. Some links may be affiliate links; this never influences our reviews or rankings.