🔹 What is L1 (Layer 1)?

Definition:

Layer 1 is the blockchain itself – the base protocol layer. Examples:

$BTC

$ETH

$SOL

On this layer:

Transactions are executed directly on the main chain.

Security, consensus, and data integrity are provided directly by the chain.

Advantages:

High decentralization and security

Usually more battle-tested and robust infrastructure

Disadvantages:

Network congestion can occur

Transaction fees may rise (e.g., Ethereum gas fees)

Limited transaction speed (e.g., Bitcoin around 7 TPS)

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🔸 What is L2 (Layer 2)?

Definition:

Layer 2 is a layer built on top of Layer 1. Purpose:

Reduce the load on L1

Make transactions cheaper and faster

How it works:

L2s aggregate and process transactions off-chain, then write the results back to L1, inheriting its security. Examples:

@arbitrum (Ethereum L2)

@Optimism

@zksync

@Starknet

@0xPolygon (some rollup solutions)

Technical approaches:

Rollups (Optimistic Rollup, ZK Rollup)

State Channels (e.g., Lightning Network for Bitcoin)

Plasma, Validium, and other alternatives

Advantages:

Low transaction fees

Faster confirmation times

Inherits security from L1 blockchains like Ethereum

Disadvantages:

More complex architecture

Wallet/user experience not always as smooth as L1

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📌 In summary

L1 = the blockchain itself, where everything happens

L2 = scales L1, enabling faster and cheaper transactions while relying on its security

🔹 What is L1 (Layer 1)?

Definition:

Layer 1 is the blockchain itself – the base protocol layer. Examples:

$BTC

$ETH

$SOL

On this layer:

Transactions are executed directly on the main chain.

Security, consensus, and data integrity are provided directly by the chain.

Advantages:

High decentralization and security

Usually more battle-tested and robust infrastructure

Disadvantages:

Network congestion can occur

Transaction fees may rise (e.g., Ethereum gas fees)

Limited transaction speed (e.g., Bitcoin around 7 TPS)

---

🔸 What is L2 (Layer 2)?

Definition:

Layer 2 is a layer built on top of Layer 1. Purpose:

Reduce the load on L1

Make transactions cheaper and faster

How it works:

L2s aggregate and process transactions off-chain, then write the results back to L1, inheriting its security. Examples:

@arbitrum (Ethereum L2)

@Optimism

@zksync

@Starknet

@0xPolygon (some rollup solutions)

Technical approaches:

Rollups (Optimistic Rollup, ZK Rollup)

State Channels (e.g., Lightning Network for Bitcoin)

Plasma, Validium, and other alternatives

Advantages:

Low transaction fees

Faster confirmation times

Inherits security from L1 blockchains like Ethereum

Disadvantages:

More complex architecture

Wallet/user experience not always as smooth as L1

---

📌 In summary

L1 = the blockchain itself, where everything happens

L2 = scales L1, enabling faster and cheaper transactions while relying on its security