Why Polkadot exists
Imagine you're planning a trip from New York to Tokyo. You book a flight with Airline A, but when you arrive at the airport, you discover that Airline A has built its own airport that only serves Airline A flights.
“Sorry,” says the airline representative. “If you want to fly with Airline B to connect to your Tokyo flight, you'll need to drive 50 miles to their airport. Each airline operates independently.”
This would be absurd, right? Yet this is exactly the problem in the blockchain world today.
Each blockchain is like an airline with its own airport. Bitcoin has its own “airport” (network), Ethereum has its own “airport,” and hundreds of other blockchains each have their own isolated “airports.”
Digital money only
Smart contracts only
Specialized functions only
The problem? These “airports” don't talk to each other. You can't easily move your Bitcoin to Ethereum, or use a smart contract on Ethereum to interact with data on another blockchain.
Polkadot is like building a universal airport that can accommodate any airline. Instead of each blockchain being isolated, Polkadot creates a network where different blockchains (called “parachains”) can:
Just like the internet connected isolated computers into a global network, Polkadot aims to connect isolated blockchains into an “internet of blockchains.”
Instead of building one blockchain to rule them all, Polkadot creates a network where specialized blockchains can work together seamlessly.
This means you could have a blockchain optimized for gaming, another for DeFi, another for identity, and they could all work together as if they were one system.
What's the main problem Polkadot solves?