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Unit 1 · Creative Development Flashcards Cheat Sheet Essentials Visual Review MC Practice FRQ Practice

AP Computer Science Principles Unit 1 Visual Review

A topic-by-topic visual walkthrough of Big Idea 1: Creative Development — collaboration, program function and purpose, the design-and-development process, and finding and fixing errors.

← Back to Unit 1 hub
TOPIC 1.1 Collaboration Why collaborate? Collaboration produces a BETTER solution than one person working alone. Diverse perspectives reveal blind spots and reduce bias in a program. Pair programming Two roles at one computer: • DRIVER writes the code. • NAVIGATOR reviews & guides. Partners swap roles regularly. Skills of effective collaboration Communication, consensus-building, conflict resolution, and giving/receiving constructive feedback. Online tools let collaborators share code and ideas even when they are not in the same place. Collaboration and diverse perspectives build better, less-biased programs. The Review Hub · AP Computer Science Principles · Big Idea 1 TOPIC 1.2 Program Function and Purpose INPUT PROGRAM OUTPUT →→ Every program has a purpose A program is written to solve a problem or express creativity for its users. Its FUNCTIONALITY is what it actually does when it runs. Inputs & outputs INPUT can come from a user, a device, a file, or another program. OUTPUT can be visual, audible, tactile, or text — how the program responds. A program serves a purpose; it takes input, processes it, and produces output. The Review Hub · AP Computer Science Principles · Big Idea 1 TOPIC 1.3 Program Design and Development THE ITERATIVE & INCREMENTAL PROCESS Investigate Design Prototype Test Reflect ↻ →→→→ Iterative & incremental ITERATIVE: repeat the cycle, refining the program each time. INCREMENTAL: build and test one piece at a time, then combine them. Plan before you code Gather requirements, then plan with diagrams, flowcharts, or pseudocode. Documentation & comments explain how code works for you and collaborators. Development is iterative and incremental — plan, prototype, test, and refine. The Review Hub · AP Computer Science Principles · Big Idea 1 TOPIC 1.4 Identifying and Correcting Errors Types of errors SYNTAX: breaks the language's rules. RUNTIME: crashes while running. LOGIC: runs but gives the wrong result. Ways to test Run with many inputs, including edge cases. Compare actual vs. expected output. Add DISPLAY statements to trace values. Debugging Debugging = finding and fixing errors. Test small pieces as you build to isolate a bug. A "test case" pairs input with expected output. Logic errors are the hardest to catch The program runs without crashing but does the wrong thing — only careful testing against expected results reveals them. Errors are syntax, runtime, or logic — test with many inputs to find and fix them. The Review Hub · AP Computer Science Principles · Big Idea 1
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How to use the visual review

Spend 30 seconds per slide before clicking next. Look at the diagram, then ask yourself: "Could I explain this idea, or name this error type, from memory?"

Use the fullscreen button () on desktop for the best experience. Use arrow keys to navigate. Tap "Show all slides" to jump around.

This is great for review the night before the exam — fast, visual, and covers every idea you need to recognize in Unit 1.