Layer 2, or Layer 2, it's like a Extra highway which is built on top of the blockchain's main road (Layer 1) so that Everything works faster and at a lower cost. Thanks to these new ways, you can send cryptocurrency, make exchanges or use apps without everything getting stuck or costing a lot of gas.

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Layer 2 (L2) refers to a set of scaling solutions built on the main blockchain (Layer 1), designed for improve the efficiency, speed and cost of transactions, without compromising the security nor the decentralization of the base protocol. These solutions work outside the main chain, but rely on it as liquidation and verification layer, thus achieving greater transactional capacity and reducing congestion.

Among the main Layer 2 technologies are:

• Rollups (Optimistic and ZK): group multiple off-chain transactions and publish them in L1 in a compact form. Examples: Arbitrum, Optimism, ZKSync, Starknet.
• State Channels: they allow multiple private transactions between parties, publishing only the final result in L1.
• Sidechains: independent blockchains that communicate with L1 through bridges, such as Polygon PoS (although technically not all of them are pure L2).

These solutions allow you to execute thousands of transactions per second (TPS) with minimum rates and quick confirmations, which is essential for scaling dApps, DeFi, NFT and gaming on networks like Ethereum, where gas costs and L1 throughput are limiting.

Layer 2 represents the ideal technical balance of the blockchain trilemma: maintains the security and decentralization of L1, while optimizing scalability, becoming a key element for mass adoption.

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