# Bitcoin

> digital cash system and associated currency

**Wikidata**: [Q131723](https://www.wikidata.org/wiki/Q131723)  
**Wikipedia**: [English](https://en.wikipedia.org/wiki/Bitcoin)  
**Source**: https://4ort.xyz/entity/bitcoin

## Summary
Bitcoin is a decentralized digital currency and payment system created by Satoshi Nakamoto, launched in 2009, that operates without central authorities using blockchain technology. It enables peer-to-peer transactions and serves as both a medium of exchange and store of value.

## Key Facts
- **Inception**: Created by Satoshi Nakamoto and launched on 2009-01-03.
- **Technology**: Uses proof-of-work consensus mechanism and operates on port 8333 (TCP).
- **Legal Status**: Recognized as legal tender in El Salvador (since 2021-09-07) and Central African Republic.
- **Symbol/Code**: Unit symbol ₿, short name BTC, with subdivisions like satoshi (1 BTC = 100,000,000 sat).
- **Market Cap**: $712,696,504,252 (as of 2023-11-14).
- **Price**: $103,331.32 USD (as of 2024-12-15).
- **Exchanges**: Traded on Binance, Kraken, Bitfinex, Huobi, and others.

## FAQs
### Q: Who created Bitcoin?
A: Bitcoin was created by an individual or group using the pseudonym Satoshi Nakamoto, who introduced it via a 2008 whitepaper titled "Bitcoin: A Peer-to-Peer Electronic Cash System."

### Q: How does Bitcoin differ from traditional currencies?
A: Bitcoin operates as decentralized digital currency without central bank oversight, using cryptography and blockchain technology for security, unlike government-issued currencies backed by physical assets or institutions.

### Q: Is Bitcoin legal?
A: Bitcoin has legal status in specific countries: El Salvador (since 2021) and Central African Republic recognize it as legal tender, though regulations vary globally and are disputed by institutions like the European Central Bank.

### Q: What powers Bitcoin's security?
A: Bitcoin uses cryptographic techniques (Elliptic Curve Digital Signature Algorithm, Schnorr signatures) and energy-intensive proof-of-work to validate transactions and secure the network.

### Q: Can Bitcoin be divided into smaller units?
A: Yes, Bitcoin subdivides into millibitcoin (mBTC), microbitcoin (μBTC), and satoshi (1 BTC = 1,000,000,000 μBTC or 100,000,000 sat).

## Why It Matters
Bitcoin pioneered decentralized finance by introducing the first viable cryptocurrency, challenging traditional banking systems through blockchain-based transparency. Its fixed supply of 21 million coins created a novel asset class for inflation hedging, while its open-source protocol inspired the broader cryptocurrency ecosystem. Adoption by nations like El Salvador highlights its potential for financial inclusion in unbanked regions, though volatility and energy consumption continue to spark debate about its long-term viability and environmental impact.

## Notable For
- First successful implementation of a decentralized cryptocurrency and blockchain technology.
- Fixed 21 million coin supply cap designed to prevent inflation.
- Adoption as legal tender by sovereign nations (El Salvador, Central African Republic).
- Proof-of-work consensus system that secures transactions via cryptographic validation.
- Pioneered cryptocurrency code standards (BTC/XBT) now used globally.

## Body

### Technical Specifications
- **Protocol**: Communication protocol (port 8333/TCP) using proof-of work and Schnorr digital signatures.
- **Algorithms**: Elliptic Curve Digital Signature Algorithm, secp256k1 elliptic curve.
- **Subdivisions**: mBTC (millibitcoin), μBTC (microbitcoin), satoshi (1 BTC = 100,000,000 sat).
- **Unit Symbol**: ₿ (Unicode character U+20BF).
- **License**: MIT License.

### Governance and Development
- **Creator**: Satoshi Nakamoto (anonymous).
- **Instance Type**: Cryptocurrency, blockchain, communication protocol, free software.
- **License Status**: Copyrighted with open-source implementation.
- **Derivatives**: Inspired altcoins like Peercoin, Bitcoin Cash, Bitcoin Gold.

### Legal and Economic Status
- **Classification**: Defined as cryptocurrency, reserve currency, and payment system by the European Central Bank (with "disputed" qualifiers).
- **Legal Tender**: Mandatory in El Salvador (2021-09-07 onward) and Central African Republic.
- **Market Data**:
  - Price: $103,331.32 USD (2024-12-15).
  - Market Cap: $712,696,504,252 (2023-11-14).
- **Symbol Codes**: BTC and XBT (ISO 4217 alternative code).

### Network and Infrastructure
- **Exchanges**: Actively traded on Binance, Kraken, Bitfinex, Huobi, KuCoin.
- **Communities**: Dedicated subreddits (Bitcoin, btc, BitcoinMarkets) and Stack Exchange site.
- **Consumption**: Estimated 18.4 gigawatts power usage (2024-02-20).

### Cultural and Academic Recognition
- **Time Earliest Record**: 2008-10-31 (whitepaper publication date).
- **Classifications**: Dewey Decimal 381.142, 332.178, 332.404; subject of academic research in economics, computer science, and mathematics.
- **Notable Work**: Cites "Chancellor Alistair Darling on brink of second bailout for banks" in its conceptual origins.