Create a cover related to this chapter of the course: "A1. DeFi Infrastructure — Wallets, Networks, and Bridges Stop Flying on Autopilot If you're reading this, chances are you've already done all of these things: connected MetaMask to a dApp, switched networks with two clicks, signed a transaction without really reading what was inside it, bridged tokens from Ethereum to an L2, and farmed a few airdrops along the way. You're not a beginner. You know how to use DeFi. But here's the uncomfortable question: do you actually understand what's happening under the hood? Most users don't. They operate on autopilot, clicking through interfaces that hide the real mechanics. That's fine until something goes wrong: a bridge gets exploited, a transaction approves more than you intended, or you send tokens to the wrong network and stare at your screen wondering where they went. Understanding the infrastructure is what separates a user who's a hostage to the interface from one who can actually evaluate risk, choose tools wisely, and recover when things break. This chapter is about that layer below the surface: the wallets that hold your access, the networks that process your transactions, and the bridges that connect everything. By the end, you'll have a much clearer mental model of what's really moving when you click "Confirm.""