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Forking & Reorganization

🌐 The Global Network Behind Blockchain

Discover how thousands of computers work together without a central authority

🌐 Blockchain Nodes & Network

A blockchain isn't stored in one place - it's distributed across thousands of computers called nodes. Let's explore how these nodes work together to maintain the network!

🎯 What is a Node?

A node is any computer that connects to the blockchain network and follows its protocol. Think of it as a network participant that helps keep the blockchain alive and secure.

Core Functions:
Validation: Verify transactions and blocks follow consensus rules
Storage: Keep a copy of blockchain data (full or partial)
Propagation: Relay new transactions and blocks to other nodes
Consensus: Participate in reaching agreement on blockchain state

🎮 Interactive Node Type Explorer

Click each node type to understand its characteristics:

🖥️

Full Node

Stores complete blockchain history and validates all transactions and blocks

Storage Required
500GB - 2TB+
Validation Level
Full validation
Bandwidth Usage
High
Key Features:
Complete blockchain copy
Independent verification
Can serve data to others
Highest security

🌍 Why Nodes Matter

🔒
Decentralization

More nodes = harder to attack or control. No single point of failure exists when thousands of nodes maintain the network.

Trust Minimization

Running your own node means you don't trust anyone else. You verify everything yourself using consensus rules.

🚀
Network Resilience

Even if thousands of nodes go offline, the remaining nodes keep the blockchain running without interruption.

🗳️
Governance Participation

Node operators signal support for protocol upgrades and changes, giving them a voice in network evolution.

📊 Node Distribution

Real-world blockchain networks have different node distributions:

Bitcoin Network
~15,000 reachable nodes

Most decentralized: Nodes spread across 100+ countries

Ethereum Network
~7,000 reachable nodes

High decentralization: Strong node distribution globally

Smaller Networks
100-1,000 nodes

Lower decentralization: More vulnerable to coordinated attacks

💡 Key Insights

🎯
Full Node = Full Control

Only by running a full node can you truly verify everything yourself without trusting third parties.

📱
Light Nodes Enable Mobile

Smartphones can't store terabytes of data. Light nodes make blockchain access practical for everyday devices.

🌐
More Nodes = More Secure

Network security increases with node count and geographic distribution. Centralized node clusters are vulnerabilities.