AP® Computer Science Principles

Flashcards

169 cards with the terms and ideas you need to know cold. The ones you find hard come back sooner.

Multiple choice practice

299 exam-style questions, timed like the real exam, with every answer explained.

Practice exam

The whole multiple choice section: 70 questions in 2 hours, weighted by unit like the real exam. A fresh mix every time.

Must-know sheet

The facts, rules and terms to know cold on exam day, on one page. Filter it by unit, or print it.

Free-response practice

20 free-response questions like the ones on the exam. Score your answer with the rubric and a model answer, or sign in for free AI scoring.

Creative Development

4 topics · 24 videos

• Teams with different backgrounds and skills catch problems one person would miss
• A program's purpose is the problem it solves; its function is what it does when it runs
• Programs are built in small steps and tested along the way
• Comments and documentation explain code and give credit to code written by others
• Testing with inputs you choose, and outputs you expect, is how you find errors

Data

4 topics · 27 videos

• All digital data is stored as bits, and the same bits can mean different things
• Each extra bit doubles the number of values you can represent
• Lossless compression can be undone exactly; lossy compression trades detail for size
• Cleaning, filtering and visualizing data turns raw data into information
• A correlation in data doesn't prove that one thing causes another

Algorithms and Programming

18 topics · 98 videos

• Every algorithm is built from sequencing, selection and iteration
• In the exam's pseudocode, ← means assignment and list indexes start at 1
• Lists and procedures are abstractions that keep programs manageable
• Binary search is usually much faster than linear search, but needs sorted data
• Some problems take unreasonable time, and some can't be solved by any algorithm

Computer Systems and Networks

3 topics · 20 videos

• The internet is a network of networks built on open protocols anyone can use
• Data travels in packets that can take different paths and arrive out of order
• The World Wide Web runs on the internet; it isn't the internet itself
• Redundant paths make the internet fault tolerant
• Parallel and distributed computing speed up big jobs, but the sequential part limits the speedup

Impact of Computing

6 topics · 37 videos

• The same innovation can help some people and harm others, sometimes in ways nobody planned
• Unequal access to devices and the internet can widen existing gaps
• Programs can repeat the human biases built into their data and design
• Creative Commons, open source and open access let people share work legally
• Strong passwords, multifactor authentication and encryption protect your data