---
title: Layer 2
url: "https://www.unknowngravity.com/en/glosario/layer-2-capa-2"
site: Unknown Gravity
published: "2025-06-07T15:14:57+00:00"
modified: "2026-07-15T10:51:28+00:00"
language: en-US
description: "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…"
section: "Home > Layer 2"
---

# Layer 2

GLOSSARY · BLOCKCHAIN & WEB3

Solutions that operate on top of a main blockchain to improve scalability and reduce costs.

WHAT IS IT? · FOR DUMMIES

**Layer 2** (L2) is like an **extra motorway** 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.

WHAT IS IT? · PRO

**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.

## 01 / Key points

- It is a solution built on top of a blockchain base (Layer 1)
- Improves speed, reduces fees and increases scalability
- Use technologies such as rollups, state channels and sidechains
- Publish your data or tests on L1 to maintain security
- Fundamental to the growth of dApps, DeFi, games and NFTs

## 02 / Advantages

- **Much lower transaction costs** What in Layer 1
- **Increased processing capacity**, with thousands of TPS
- **Reducing congestion on the main network**
- **Compatibility with L1 security and liquidity**
- **Ideal for mass-use products such as DeFi, marketplaces or Web3 games**

## 03 / Disadvantages

- **Additional technical complexity** for users and developers
- **Risks of centralization or dependence on sequencers** in some cases
- **Withdrawal may take time (especially in Optimistic Rollups)**
- **Lack of standardization between solutions**, making interoperability difficult
- **Vulnerability in bridges or interlayer infrastructures**

RELATED CONCEPTS

[Layer 1](/en/glosario/layer-1-capa-1) [State Channel](/en/glosario/state-channel) [ZK Proof (Zero-Knowledge Proof)](/en/glosario/zk-proof-zero-knowledge-proof) [Interoperability](/en/glosario/interoperabilidad)

KEEP LEARNING

[Which blockchain suits me? A clear comparison of Ethereum, Arbitrum and Base](/en/articulos/que-blockchain-me-conviene-comparativa-clara-entre-ethereum-arbitrum-y-base) [How to protect your digital assets in the cryptocurrency world](/en/articulos/como-proteger-tus-activos-digitales-criptomonedas) [Tokenomics that work: How to design an economy that doesn't collapse in 6 months](/en/articulos/tokenomics-que-funcionan-como-disenar-una-economia-que-no-se-derrumbe-en-6-meses) [Why are your users leaving your dApp? 5 keys to improving the UX of your dApp](/en/articulos/claves-mejorar-ux-dapp) [Comparison of smart contracts programming languages](/en/articulos/lenguajes-programacion-smart-contracts)

RELATED SERVICES

[Web3 Development](/en/servicios/desarrollo-web3) [Development for Ethereum (EVM)](/en/servicios/desarrollo-para-ethereum-evm) [DeFi protocols](/en/servicios/protocolos-defi) [Blockchain consulting for companies](/en/servicios/consultoria-blockchain) [Smart contract auditing](/en/servicios/blockchain-security-audits)

[Full glossary](/en/glosario)

This entry is informative. It is not legal, tax or investment advice. The rules cited change: check the current version on [BOE](https://www.boe.es) and [EUR-Lex](https://eur-lex.europa.eu).