# Understanding Networks and Layers

A network is a system of interconnected devices or nodes that are able to communicate with one another. In the context of Ethereum, a network refers to the environment where users can test, develop, and interact with smart contracts and decentralized applications (dApps).

There are different Ethereum networks available, each with their own unique characteristics. The most widely used networks include the Ethereum Mainnet, the Ethereum Testnet, and Layer 2 networks.

The Ethereum Mainnet is the original and primary blockchain network where on-chain transactions occur. This is where real Ether (ETH) is used to pay for transaction fees, and where smart contracts and dApps are deployed and executed. **This is also referred to as Layer 1**.

**Layer 2 networks**, on the other hand, are additional networks that operate on top of the Ethereum Mainnet, and offer faster and cheaper transactions. These networks use off-chain transactions, which means that they do not need to be recorded on the Ethereum Mainnet, thus reducing the cost and time of transactions. Examples of Layer 2 networks include Optimism and Arbitrum.

The **BNB Chain** is a blockchain platform that is compatible with the Ethereum Virtual Machine (EVM). This means that developers can use familiar programming languages, such as Solidity, to write smart contracts and deploy them on the BNB Chain. This compatibility allows developers to easily port their existing Ethereum-based projects to the BNB Chain giving them access to the high-performance and low-cost transactions offered by the BNB Chain.


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