This resource includes a 10-page “What to Know” study guide for differential calculus, designed for students in a Calculus AB course or similar introductory calculus course. It consists of concise summary notes that organize the key ideas, formulas, and theorems for limits, derivatives, and their main applications in a clear, student-friendly format—ideal for unit tests, final exams, and end-of-semester review. Topics include all the high points from Units 1 through 5: Limit notation, limit laws