In Hack School 3: Building APIs with Express, we’ll explore the backend side of web development and how it powers the frontend you’ve already built. You’ll learn how to set up a basic Express server, create your first GET and POST routes, and send data as JSON, the format websites use to talk to each other. We'll cover how frontend apps interact with APIs, and if time allows, hook up a simple frontend to test it live. No database, no stress, just clean, beginner-friendly backend fundamentals that connect to the web app we've been building throughout Hack School.