Educational content, not investment advice. Crypto-asset values fluctuate.

Modulis 0 · Crypto basics
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Bitcoin — the first and largest cryptocurrency

Video · 2 min.
Bitcoin: digital gold

Grandma's gold ring is limited, not in a bank vault and independent of banks. Bitcoin is the same, only digital: 21 million in total, with the miner reward cut in half every four years. But every network is a separate world, so BTC sent to a Solana address never arrives. We also look at how to send safely, and why wBTC is not real BTC.

Narrated, with light music
The full lesson with numbers and rules is below.
Watch on YouTube

Key facts

AttributeValue
CreatedJanuary 3, 2009
CreatorSatoshi Nakamoto (pseudonym)
Max supply21,000,000 BTC
Mined so far~20M BTC (>95%)
Block time~10 minutes
ConsensusProof of Work (solving cryptographic puzzles)
PurposeStore of value, P2P money

Why "digital gold"?

Bitcoin shares similar properties with gold:

GoldBitcoin
Limited supplyLimited (21M)
Expensive to mineExpensive to mine
GlobalGlobal
Inflation hedgeInflation hedge
Hard to counterfeitPractically impossible to counterfeit
Hard to fakeCryptographically secured

The difference: Bitcoin is easy to send around the world. Gold isn't.

Halving — why it matters

Every 4 years, the miner reward is cut in half:

EraYearsBlock rewardTotal BTC created per day
12009–201250 BTC7,200
22012–201625 BTC3,600
32016–202012.5 BTC1,800
42020–20246.25 BTC900
52024–20283.125 BTC450
The halving effect

After each halving, BTC's price has historically risen for 1–2 years, driven by the drop in new supply — a pattern that has now repeated 4 times.

A historical pattern isn't a guarantee of the future. Think of it as a tool: you spot a repeating pattern → you ask "what's driving it?" Here the answer is simple — shrinking new supply against steady demand. That question is what lets you judge any market headline for yourself.

The Bitcoin network vs other networks

Every network is a separate world

Bitcoin is its own blockchain — separate from Ethereum, Solana, Cardano. That gives you one clear rule you'll quickly master:

Bitcoin network characteristics

Layer 2 solutions

For faster and cheaper transactions:

How to acquire BTC

Via a CEX (centralized exchange — simplest)

1. Check the ESMA MiCA CASP register to confirm the exchange is licensed in the EU
2. Open an account at a licensed exchange (Kraken, Bitvavo, Bitstamp, Coinbase, Revolut)
3. Complete KYC (identity verification — passport/ID photo)
4. Deposit euros via SEPA (1-2 business days) or by card
5. Click "Buy BTC"
6. Fee: 0.1-1.5%
Nexo is not a licensed exchange in its own right

Nexo does not hold a MiCA CASP licence in its own name — it serves the EEA through licensed partners (Tangany GmbH, DLT Finance). The key nuance: Earn rewards and crypto-backed loans fall outside the scope of those partners' permissions.

So the first step in choosing an exchange is not the marketing but the ESMA CASP register: if a provider is not on it, there is no EU cover either. Position as of 2026-09; the register is updated, so check it yourself.

Via a DEX (decentralized exchange — more complex, but no middleman)

In the Solana ecosystem you can buy wBTC (wrapped BTC):

  1. Send SOL from a licensed exchange to Jupiter Wallet
  2. Swap SOL → wBTC via Jupiter
  3. Important distinction: this isn't real BTC, it's a token representing BTC on the Solana network

Our recommendation: buy real BTC at an EU exchange that holds a MiCA CASP licence (Kraken, Bitvavo, Bitstamp, Coinbase, Revolut) and move it to a dedicated Bitcoin wallet or a hardware wallet. Nexo does not hold a MiCA CASP licence of its own — it operates through partners (Tangany, DLT Finance), and its Earn and lending products sit outside those licences. Jupiter Wallet only works on the Solana network — it doesn't hold real BTC.

Address formats

Bitcoin has several address types:

FormatExampleUsage
Legacy (P2PKH)1A1zP1eP5...Old, more expensive
Script (P2SH)3J98t1WpEZ...Multi-sig, medium
SegWit (Bech32)bc1qxy2kg...New, cheapest ✅
Taproot (Bech32m)bc1pxy2kg...Newest, privacy

All formats work — you can send BTC to any of them. But fees and features differ.

Where to hold Bitcoin?

Holding BTC in our strategy

Jupiter Wallet only works on the Solana network, MetaMask on Ethereum and, since 2026, Solana. Neither of them holds real Bitcoin.

Hold Bitcoin in one of these places:

  • Hardware wallet (Ledger, Trezor) — the safest option, for large and small amounts alike
  • Dedicated Bitcoin wallet (e.g. Sparrow, BlueWallet)
  • A MiCA-licensed EU exchange (Kraken, Bitvavo, Bitstamp, Coinbase, Revolut) — simple to start with, but the keys stay in the exchange's hands

Our active DeFi strategy runs on Solana (Jupiter Wallet) and Ethereum (MetaMask), while BTC is held separately as a "store of value."

What you control when holding Bitcoin

Five things you control yourself — each has a simple fix:

  • Mixing up networks → send BTC only to a bc1... address; test with $5 the first time, not $5,000
  • Seed phrase (your secret recovery phrase) → write it on paper, not on a screen — it's your key, and only yours
  • Phishing → check the URL (jup.ag, not jup-wallet.app); type it into the address bar yourself, don't click through links
  • Custody → hold real BTC in a hardware wallet or a dedicated Bitcoin wallet, not on an exchange and not in wrapped tokens
  • Taxes → in Lithuania, since 2026 BTC profit is taxed at 15% GPM up to 12 average salaries (€27,745.80) a year and at a progressive 20/25/32% above that; under €2,500 a year is not declared. Set up your record-keeping in advance (CoinTracking, Koinly). Not tax advice — check vmi.lt

You'll learn to check each of these in a few seconds. These aren't dangers to fear — they're the wheel you're holding.

Once these five things become habit, you can confidently move any amount of BTC — not because "nothing can go wrong," but because you control every lever yourself.

Summary

Quick check
What is the maximum amount of Bitcoin that will ever exist?
Practice task
0 / 5
Check Bitcoin's limited supply live

In this lesson you read that there will never be more than 21 million BTC. Check that against real data — takes about 5 minutes, nothing to buy.

This is learning, not investing — use only small amounts you treat as tuition.

You just checked Bitcoin's supply and block reward straight from the network and compared them with the halving table — now you read network data yourself, not through headlines.

What is cryptocurrencyEthereum vs Solana
Mark as read

Support

Free material is easy to put off

Something practice teaches: when you paid nothing to learn, it is easy to postpone learning indefinitely. If these lessons actually gave you something — saved you a mistake, or explained what nobody else did — you can pay whatever you think they were worth.

This is not a price, a subscription, or a fee for access. The amount is yours to choose, and paying nothing is entirely fine.

Solana address

CUj6wYQLSBxidzm7Lqtkxbw2d8Sv2H2tbJELyAjR756M

Solana network only

Send SOL or SPL tokens (e.g. USDC) only on the Solana network. Sending from an exchange over a different network loses the funds permanently — nobody can recover them.

What you get for it

Nothing extra, and that is deliberate. Every lesson, all three difficulty levels and every calculator stay free and sign-up-free, with or without a donation. There is no gated section, no share of profits, no future token and no claim on anything.

Where the money goes

A donation becomes my own money. I use it to keep the site running and to fund a public demonstration position on a lending protocol — real money, so the lessons have something to show instead of only theory. I publish the results, losses included, publicly and free for everyone. It is my position and my risk, not a pooled fund.

This is a gift for content already received, not an investment and not a payment for a service. Non-refundable. Educational content, not an investment recommendation.