The Ethereum ecosystem has experienced significant growth over the last few years. With growing demand for dApps, NFTs, and block space, users are paying hefty fees to use the congested network. In 2021, when the price of $ETH was settling around $3,000, users were spending $100+ on gas fees for one transaction alone. Along come Layer 2s (L2), Layer 2 refers to a network that runs on top of L1s to improve scalability and efficiency while reducing bottlenecks of transaction costs from the underlying L1 chain. Layer 2 protocols aim to solve the problems of high fees and slow transactions by finding ways to ease the network load. To learn more about Layer 2s and Optimistic Roll-ups see the sources section at the bottom.