1. First Principles of Version Control & GitHub

Before this guide touches a single GitHub feature, you need the mental model underneath all of them: what version control actually does, how Git and GitHub divide the work, and the three building blocks — repositories, commits, and branches — that every later phase assumes you already understand. Skim this phase and the rest of the exam will feel like vocabulary. Skip it and every later phase will feel like memorization.

Think of this phase as the glossary every later phase assumes you've already internalized — skip it, and everything downstream turns into rote memorization instead of logic, which is exactly what the exam tests first. ⚠️ Exam Trap: candidates who treat Git and GitHub as interchangeable, or assume a commit is automatically saved to GitHub, lose points here before the exam even gets to harder material.