AP Computer Science Principles (CSP) Study Prep Guide

A complete prep resource for the AP CSP exam — covering Big Ideas, vocabulary, example questions, pseudocode, and strategies.

Table of Contents

  1. Exam Overview
  2. Big Ideas
  3. Unit-by-Unit Breakdown
    • Unit 1: Digital Information
    • Unit 2: The Internet
    • Unit 3: Algorithms & Programming
    • Unit 4: Big Data & Privacy
    • Unit 5: Impacts of Computing
  4. Essential Vocabulary
  5. Pseudocode & Algorithms
  6. FRQ Practice & Strategy
  7. MCQ Practice Tips
  8. Exam Day Advice
  9. Additional Resources

Exam Overview

  • Format
    • Multiple Choice: 70 questions, 2 hours
    • Create Task: Submit before exam (30%)
  • Weight
    • Multiple Choice (70%)
    • Create Task (30%)
  • Skills Tested
    • Algorithms, Programming, Data, Internet, Global Impact

Big Ideas

  1. Creative Development — How programs are developed & improved.
  2. Data — Storing, representing, and analyzing information.
  3. Algorithms & Programming — Designing and implementing solutions.
  4. Computer Systems & Networks — Internet, protocols, and cybersecurity.
  5. Impact of Computing — Ethics, bias, digital divide, and global effects.

Unit-by-Unit Breakdown

Unit 1: Digital Information

  • Key Ideas
    • Binary (base 2), bits/bytes
    • Lossless vs. lossy compression
    • Representing text, images, audio
  • Vocabulary
    • Bit, Byte, Overflow error, Round-off error, Sampling
  • Practice Q
    • Q: What is the main difference between lossy and lossless compression?
      • Answer: Lossless preserves all data; lossy discards some data to save space.

Unit 2: The Internet

  • Key Ideas
    • IP addresses (IPv4 vs IPv6)
    • DNS, TCP/IP, Packets
    • Cybersecurity basics (encryption, HTTPS, phishing)
  • Vocabulary
    • Bandwidth, Latency, Protocol, Fault tolerance
  • Practice Q
    • Q: What protocol guarantees delivery of data packets?
      • Answer: TCP

Unit 3: Algorithms & Programming

  • Key Ideas
    • Variables, conditionals, iteration
    • Procedures with parameters
    • Searching (linear, binary) & sorting algorithms
  • Vocabulary
    • Abstraction, Algorithm, Selection, Iteration, Efficiency
  • Practice Q
    • Q: What is the difference between a parameter and an argument?
      • Answer: A parameter is defined in the procedure; an argument is the value passed in.

Unit 4: Big Data & Privacy

  • Key Ideas
    • Data collection, storage, analysis
    • Moore’s Law
    • Encryption (symmetric vs asymmetric)
  • Vocabulary
    • Metadata, Public key encryption, Digital certificate
  • Practice Q
    • Q: Why is metadata valuable in large datasets?
      • Answer: It provides context about data (time, source, etc.), enabling deeper analysis.

Unit 5: Impacts of Computing

  • Key Ideas
    • Digital divide
    • Bias in computing
    • Intellectual property & ethics
  • Vocabulary
    • Crowdsourcing, Open source, Digital divide, Creative Commons
  • Practice Q
    • Q: What is the “digital divide”?
      • Answer: The unequal access to computing resources across different groups.

Essential Vocabulary

  • Abstraction — Reducing complexity by hiding details.
  • Algorithm — A set of instructions to solve a problem.
  • API — A collection of commands/functions made available to a programmer.
  • Iteration — Repeating a set of instructions (loops).
  • Packet — Small chunk of data sent over a network.
  • Symmetric vs Asymmetric encryption — Single key vs. public/private key pairs.
  • Heuristic — Problem-solving approach that finds an approximate solution when exact solution is impractical.

FRQ Practice & Strategy

  • Tips
    • Always explain reasoning in words + pseudocode.
    • Define procedures with parameters clearly.
    • Trace through code to predict outputs.

MCQ Practice Tips

  • Eliminate obvious wrong answers first.
  • Watch out for off-by-one errors in iteration.
  • If you see “most efficient,” think binary search, sorting, or abstraction.
  • Cybersecurity questions often ask about encryption or fault tolerance.

Exam Day Advice

  • Sleep well — don’t cram last minute.
  • Use the reference sheet for pseudocode (provided by College Board).
  • Manage time: ~1.7 min per MCQ.
  • For FRQs, focus on clarity, not fancy code.

Additional Resources

Progress Tracker

  • Unit 1 studied
  • Unit 2 practiced
  • Unit 3 coding practice complete
  • Unit 4 FRQs reviewed
  • Unit 5 notes memorized

AP CSP Practice Multiple Choice Quiz

Big Ideas 1, 2, 4, and 5
20 Questions — Practice for Exam

Instructions

  • Select ONE best answer per question.
  • Covers: Creative Development (BI1), Data (BI2), Algorithms & Programming Concepts (BI4, but no coding required), and Impact of Computing (BI5).

Questions

1. Which of the following best describes an abstraction?

  • A specific set of code instructions
  • A simplified representation of something complex
  • The physical hardware of a computer
  • A unique identifier for internet communication

2. A team is designing an app that tracks exercise habits. Using a flowchart instead of writing detailed text is an example of:

  • Data compression
  • Visualization
  • Iteration
  • Abstraction

3. Which of the following is the smallest unit of digital data?

  • Byte
  • Megabyte
  • Kilobyte
  • Bit

4. Which scenario best represents crowdsourcing?

  • A single researcher collects data about climate change.
  • Volunteers worldwide contribute photos to help train an AI system.
  • A company hires contractors to work on a mobile app.
  • A student creates a personal website.

5. Which of the following is a potential harm of digital data collection?

  • It enables personalization in online services.
  • It can introduce bias in decision-making algorithms.
  • It allows compression of files for faster transfer.
  • It increases accessibility of educational resources.

6. A large image is compressed before being sent over email. Which is most likely true about the compression?

  • It removes all colors from the image.
  • It may lose some detail but reduces file size.
  • It increases the file size.
  • It changes the image into text form.

7. Which is an example of an algorithm?

  • The order of steps to bake a cake
  • The physical ingredients used in baking
  • The oven that heats the cake
  • The flavor of the finished cake

8. Which of the following demonstrates the digital divide?

  • A student in a rural area lacks reliable internet access.
  • A website is written using multiple programming languages.
  • A file is saved in both .docx and .pdf formats.
  • An app is updated with new features.

9. A health organization collects daily step counts from thousands of participants. Which benefit of large data sets does this show?

  • They eliminate all possible errors.
  • They allow researchers to identify patterns and trends.
  • They prevent data privacy issues.
  • They are impossible to visualize.

10. Which statement about online security is true?

  • Using the same password everywhere increases safety.
  • Strong encryption helps protect sensitive information.
  • Public Wi-Fi is always safe for banking.
  • Data breaches are impossible with cloud storage.

11. A city uses simulations to predict traffic flow. Which is a limitation of such simulations?

  • They can only run on paper.
  • They may not account for all real-world variables.
  • They cannot be based on real data.
  • They always give perfectly accurate predictions.

12. Which of the following is an example of iteration?

  • A student writes a paper once without revising.
  • A loop repeats until a condition is met.
  • A phone sends a single text message.
  • A diagram shows the steps of a process.

13. Which computing innovation most directly supports global collaboration?

  • A local-only text editor
  • Cloud-based document sharing
  • A standalone calculator
  • An offline video game

14. Which of the following is an example of metadata?

  • The words in an email
  • The time and date the email was sent
  • The meaning of the email
  • The opinion expressed in the email

15. Which best explains why Internet protocols are layered (like TCP/IP)?

  • To make data less secure
  • To reduce abstraction
  • To allow systems to be designed independently but work together
  • To ensure that only one company controls the Internet

16. Which of these is a trade-off of using a lossy compression technique?

  • Smaller file size but permanent loss of some data
  • Larger file size but better image quality
  • Slower transmission but identical copy
  • No change in file size but faster processing

17. Which of the following is an example of bias in computing?

  • An AI system produces different results for different demographic groups.
  • An app correctly translates text into multiple languages.
  • A photo-sharing platform compresses images for speed.
  • A database includes millions of rows of data.

18. Which statement best explains why open data sets are valuable?

  • They always guarantee privacy.
  • They allow many people to analyze and build on the same information.
  • They prevent crowdsourcing.
  • They can never contain errors.

19. A social media app sends notifications when friends post updates. Which computing concept does this demonstrate?

  • Simulation
  • Event-driven programming
  • Sequencing
  • Data compression

20. Which of the following is a safe computing practice?

  • Using personal data without user consent
  • Regularly updating software to patch vulnerabilities
  • Sharing login credentials with multiple people
  • Disabling all security features for faster access

📌 Answer Key

Click to expand 1. B 2. D 3. D 4. B 5. B 6. B 7. A 8. A 9. B 10. B 11. B 12. B 13. B 14. B 15. C 16. A 17. A 18. B 19. B 20. B