What is Cryptocurrency?
Cryptocurrency is digital, cryptographically secured money that moves peer-to-peer on blockchains. You'll learn core traits, why Bitcoin started it all, and how wallets and transactions work.
Who Is This For?
- •Curious beginners who haven't bought crypto yet
- •Anyone wondering why crypto matters beyond price
Learning Objectives
- 1.Define cryptocurrency and its key characteristics
- 2.Explain how wallets, addresses, and transactions fit together
- 3.Describe why crypto enables global, open value transfer
Key Characteristics
Cryptocurrency combines several revolutionary properties that make it fundamentally different from traditional money.
Digital-Only
No physical coins or bills. Exists purely as data on the blockchain.
Unlike gold or cash, crypto has no physical form—but that's a feature, not a bug.
Cryptographically Secured
Math protects your ownership. Private keys prove control over funds.
Breaking the encryption would require more computing power than exists on Earth.
Decentralized
No single bank or government controls it. Network of peers maintains it.
Thousands of nodes worldwide ensure no single point of failure or control.
Peer-to-Peer
Send value directly to anyone, anywhere, without intermediaries.
Like handing someone cash, but works across the internet globally.
🔄 Traditional vs Peer-to-Peer
The Bitcoin Origin Story
Bitcoin was the first cryptocurrency, launched in 2009 by the pseudonymous Satoshi Nakamoto. It solved the "double-spend problem" without needing a trusted third party.
📜 Key Milestones
📊 Bitcoin's Fixed Supply
Only 21 million Bitcoin will ever exist. New coins are created through mining, with the reward halving every ~4 years. Drag the slider to see the supply over time.
The last Bitcoin will be mined around the year 2140
🥇 Why Digital Gold?
Like Gold:
- • Scarce and finite supply
- • Requires energy to "mine"
- • Used as store of value
- • Not controlled by governments
Better than Gold:
- • Easily divisible (8 decimals)
- • Instantly transferable globally
- • Verifiably scarce (check the code)
- • Can't be counterfeited
How It Works Day to Day
Understanding wallets, addresses, and transactions is essential for using crypto safely. Let's demystify these concepts.
🔑 Keys, Addresses & Wallets
Click through to see how private keys, public keys, and addresses relate to each other:
Private Key
Your secret—never share it!
••••••••••••••••••••••••••••••••••••••••••••••••••••A random 256-bit number. Anyone who knows it controls your funds. Treat it like your bank vault key.
🧪 Try It: Transaction Flow
Watch how a cryptocurrency transaction moves from your wallet to the blockchain:
Common Mistakes & Gotchas
These misconceptions can lead to lost funds or security issues. Learn from others' mistakes!
⚠️ Golden rule: When sending to a new address for the first time, always send a tiny test amount first. Verify it arrives, then send the full amount. This small precaution has saved countless people from costly mistakes.
Knowledge Check
Let's see how well you understand cryptocurrency basics. Answer all 5 questions below.
What does a crypto wallet actually store?
Why is Bitcoin often called 'digital gold'?
Who confirms transactions on a blockchain?
What is the maximum supply of Bitcoin that will ever exist?
What happens if you lose your private key?