Layer 1s & 2s
How blockchains scale — the city and the high-speed train
Layer 1s & 2s
Let's say that blockchains are like cities.
A Layer 1 is the main city. It's where everything happens. People live there, build things, and make everyday transactions. Every smart contract is like a new building. Every action has to go through city traffic and be approved by city officials, who act like validators.
Each Layer 1 blockchain, like Ethereum, Bitcoin, or Solana, is its own city, with its own laws, road systems, and record-keeping methods.
Consensus Mechanisms
To keep everyone honest, Layer 1s use something called a consensus mechanism. This is how they make sure everyone agrees on what's true.
But there's a limit. As more people start using these blockchains, they get crowded. The roads fill up. Traffic slows down. Fees rise.
To give you some perspective: Ethereum handles around 15 to 30 transactions per second. Visa handles thousands. So if blockchains are going to support millions of people, they need help.
Layer 2s: The High-Speed Train
A Layer 2 is like a high-speed train system built on top of the city. It doesn't replace the city. It connects to it and helps it handle more people. Most of the activity happens on the train, not in city traffic. But the city still keeps the final record of everything.
Say you and 50 friends are sending money to each other all day. If every payment goes through the city, you'll clog the roads. But if you keep track in a shared notebook and send one final update to the city at the end of the day, things move faster. That's how a Layer 2 works.
Types of Layer 2s
Some people are now exploring Layer 3s — special-purpose shuttles built on top of Layer 2s for specific apps like games or private networks.
If you remember one thing: Layer 1s keep things secure. Layer 2s make things usable. Together, they make blockchains work.