When you use Ethereum, you’re not just sending crypto—you’re running code on a global computer. But that computer gets crowded. Ethereum L2, a set of scaling technologies built on top of Ethereum to handle more transactions faster and cheaper. Also known as Layer 2, it’s not a replacement—it’s an upgrade that keeps Ethereum secure while fixing its biggest problems: slow speeds and expensive fees. Without L2, simple swaps cost $20, waits take minutes, and DeFi apps feel like dial-up internet. With L2, you get near-instant trades for pennies, and that’s why nearly every major DeFi project now runs on one.
There are different types of L2s, but they all follow the same idea: do the heavy lifting off the main chain, then prove it’s valid back on Ethereum. Optimistic Rollups, a type of Layer 2 that assumes transactions are valid unless challenged. Also known as ORUs, they’re used by Arbitrum and Optimism—two of the most popular L2s today. Then there’s ZK-Rollups, a more advanced type that uses cryptographic proofs to verify batches of transactions instantly. Also known as ZKPs, they’re the backbone of zkSync and StarkNet, offering faster finality and lower costs. Both types let you interact with Ethereum apps without paying Ethereum’s gas prices. They’re not magic—they’re engineering. And they’re the reason DeFi isn’t dead, even when Ethereum is congested.
Real users aren’t just trading on Ethereum anymore—they’re on L2s. You’ll find most active wallets, DEXs, and lending platforms running on Arbitrum or Polygon. Even big names like Uniswap and Aave moved their main operations there. That’s because people care about speed and cost, not the technical details. But here’s the catch: not all L2s are equal. Some are bloated with fake volume. Others have weak security. And a few are just rebranded sidechains pretending to be true L2s. That’s why the posts below dig into what’s real, what’s hype, and what you should actually be using in 2025. You’ll find breakdowns of the top chains, warnings about fake projects hiding behind L2 branding, and real-world comparisons that show where your money works best. No fluff. Just what matters.
Execution layers handle fast, low-cost transactions and smart contracts, while settlement layers verify them and ensure security. Together, they power today's scalable blockchains like Ethereum L2s.
