0%
Level 1: Foundations

Bitcoin Explained Simply

Everything you need to know about the first cryptocurrency.

8 min read
Bitcoin (BTC)
The first decentralized cryptocurrency, created in 2009 by the pseudonymous Satoshi Nakamoto. It introduced blockchain technology and operates as a peer-to-peer electronic cash system without central authority.

Historical Context

2008
Satoshi Nakamoto publishes the Bitcoin whitepaper during the global financial crisis
2009
The first Bitcoin block ("genesis block") is mined; first transaction occurs
2010
First real-world transaction: 10,000 BTC for two pizzas (now worth hundreds of millions)
2011
Satoshi Nakamoto disappears; Bitcoin community continues development

Simple Analogy

Think of Bitcoin like digital gold:

  • Scarce: Only 21 million will ever exist (like gold's limited supply)
  • Mined: New Bitcoin is created through computational work (like mining gold)
  • Divisible: Can be split into tiny pieces (satoshis = 0.00000001 BTC)
  • Durable: Cannot be destroyed or counterfeited
  • Portable: Can be sent anywhere instantly (unlike physical gold)

How It Works

Bitcoin Mining Process

1
Transactions are submitted
Users broadcast Bitcoin transactions to the network.
2
Miners compete
Mining computers race to solve a complex mathematical puzzle (Proof of Work).
3
Winner creates block
The first miner to solve the puzzle adds the new block of transactions to the blockchain.
4
Network verifies
Other nodes verify the solution is correct and the transactions are valid.
5
Miner is rewarded
The winning miner receives newly created Bitcoin (currently 3.125 BTC per block) plus transaction fees.

Key Features

Fixed Supply

Maximum 21 million BTC will ever exist. About 19.5 million have been mined. The last Bitcoin will be mined around year 2140.

Halving Events

Mining rewards cut in half every ~4 years (210,000 blocks). This reduces new supply over time, creating scarcity.

Decentralized

No company, government, or individual controls Bitcoin. Thousands of nodes worldwide maintain the network.

Transparent

All transactions are publicly visible. Anyone can audit the entire history of every Bitcoin ever moved.

Bitcoin's Role Today

Store of Value

Often called "digital gold" — used as a hedge against inflation and currency devaluation.

Settlement Layer

Large value transfers between institutions and countries.

Reserve Asset

Some corporations and countries hold Bitcoin as part of their treasury.

Main Risks
  • Extreme volatility: Price has dropped 80%+ multiple times in history
  • Regulatory risk: Governments could restrict or ban usage
  • Technical risk: Potential (though unlikely) vulnerabilities could be discovered
  • Competition: Other cryptocurrencies or technologies could reduce relevance
  • Environmental concerns: Proof of Work mining uses significant energy
What Beginners Should Remember
  • Bitcoin was the first cryptocurrency and remains the largest by market cap
  • Its fixed supply is a key feature that differentiates it from traditional currencies
  • Bitcoin is primarily used as a store of value, not everyday payments
  • You don't have to buy a whole Bitcoin — you can buy fractions (satoshis)