Layer (blockchain layer) is a level in the blockchain ecosystem architecture that is responsible for a specific set of functions — from core infrastructure and the base blockchain itself to scaling solutions and user-facing applications.
1️⃣Layer 0 (Infrastructure Layer)
The foundation that connects different blockchains and enables them to interact with each other.
What it does: cross-chain communication, building an ecosystem for other blockchains.
📌 Examples:
Polkadot — connects multiple blockchains through parachains.
Cosmos — an ecosystem of blockchains connected via IBC (Inter-Blockchain Communication).
Avalanche Subnets — allows creating custom blockchains within the Avalanche network.
2️⃣ Layer 1 (Base Blockchain)
These are the core networks where transactions are recorded and smart contracts run.
What it does: consensus, data storage, security.
📌 Examples:
Bitcoin — value storage and transfer (classic blockchain).
Ethereum — smart contracts, NFTs, DeFi.
Solana — fast and low-cost transactions, popular for Web3 games.
TON, BNB Chain, and others — also Layer 1 blockchains.
3️⃣ Layer 2 (Scaling on top of Layer 1)
Solutions designed to make Layer 1 faster and cheaper.
What it does: processes transactions off the main chain and then settles the final result on L1.
📌 Examples:
Lightning Network (for Bitcoin) — fast and low-fee payments.
Arbitrum (for Ethereum) — optimistic rollups.
Optimism (Ethereum) — faster transactions with minimal fees.
zkSync — zk-rollups for Ethereum.
4️⃣ Layer 3 (Applications)
These are services and applications built on top of blockchains.
What it does: end-user products — DeFi, NFTs, DAOs, games.
📌 Examples:
Uniswap — decentralized exchange (DEX).
Aave — crypto lending and borrowing.
OpenSea — NFT marketplace.
Axie Infinity — blockchain-based game.
⛏️ In summary, blockchain layers form a modular architecture where each level solves a specific task — from technical foundations and security to convenient applications for end users.
@web3frens