**Layer 1 and Layer 2: The Evolution of Blockchain Technology**

With the development of blockchain technology, the terms Layer 1 and Layer 2 have emerged to describe the various layers of this technology. In this article, we will examine in detail the differences between Layer 1 and Layer 2, discuss the advantages and disadvantages of each, and try to understand the role of these layers in the blockchain ecosystem.



**I. Fundamentals of Blockchain Technology: Layer 1**

*Layer 1 refers to the underlying blockchain protocols. This layer contains the blockchain protocols that form the basis of cryptocurrencies. Here are the key features of Layer 1:*

**1.1. Blockchain Foundation:**
- Layer 1 contains the primary blockchain protocols. Cryptocurrencies such as Bitcoin and Ethereum are examples of this layer.
- These blockchains enable the transfer of digital assets by securely recording transactions and offering a decentralized structure.

**1.2. Consensus Mechanisms:**
- Layer 1 includes different consensus mechanisms. Consensus algorithms such as Proof-of-Work (PoW), Proof-of-Stake (PoS), and Delegated Proof-of-Stake (DPoS) constitute the diversity of this layer.

**1.3. Decentralized Applications (DApps):**
- Layer 1 allows the development of decentralized applications. By supporting smart contracts, it provides a programmable and secure environment.


**II. Scalability Problem and Layer 2 Solutions**

*Scalability, one of the main problems faced by Layer 1, has been tried to be addressed with Layer 2 solutions.*

**2.1. Scalability Problem:**
- Layer 1 protocols have limited processing capacity, which affects the performance of the network under high demand.
- Increasing number of users and demand may reduce transaction speed on the blockchain and increase transaction fees.

**2.2. Layer 2 Solutions:**
- Layer 2 refers to scalability solutions built on top of Layer 1. These solutions aim to increase the number of transactions on the blockchain.
- Layer 2 is designed to solve the scalability problem and enable faster, cheaper and more efficient operations.

**III. Key Differences Between Layer 1 and Layer 2**

**3.1. Processing Speed and Capacity:**
- Layer 1 includes the underlying blockchain protocols and directly impacts transaction speed and capacity.
- Layer 2 provides a faster and scalable structure by solving transactions over Layer 1.

**3.2. Transaction Fees:**
- Layer 1 generally determines transaction fees based on demand and usage. There may be an issue of increased transaction fees during peak times.
- Layer 2 aims to perform transactions more cheaply, which provides cost advantages to users.

**3.3. Security Model:**
- Layer 1 has its own security model, and Layer 2 solutions often inherit the security of Layer 1.
- The security of Layer 2 depends on the security of Layer 1 because Layer 2 works by validating transactions on Layer 1.

**IV. In Which Situations Should It Be Used?**

**4.1. Layer 1:**
- Layer 1 includes the underlying blockchain protocols and major consensus mechanisms. It is especially used if a completely secure and decentralized environment is required.
- Suitable for the development of decentralized applications and basic transfers of cryptocurrencies.

**4.2. Layer 2:**
- Layer 2 is designed to overcome scalability issues and support faster transactions.
- It can be preferred in cases of intensive use and when low-cost operations are required. It is especially suitable for microtransactions and fast payment systems.

**V. Sample Applications and Projects**

**5.1. Layer 1 Projects:**
- Bitcoin (BTC): The first cryptocurrency and Layer 1 protocol.
- Ethereum (ETH): Layer 1 blockchain that supports smart contracts.

**5.2. Layer 2 Projects:**
- Lightning Network: Layer 2 solution built on Bitcoin, aiming to accelerate microtransactions.
- Optimistic Rollup: Working on Ethereum, aiming to increase scalability