AP CSP Vocabulary List - 150+ Terms (PDF)

Complete Vocabulary List — 145 Terms

All 5 Big Ideas • Exam-Aligned Definitions • Instant PDF Download

Abstraction	Simplifying complex systems by focusing on high-level details and hiding lower-level implementation.
Algorithm	A finite set of instructions that accomplish a specific task.
Bias	A systematic error in design, data, or reasoning that skews results or decisions.
Code Segment	A collection of program statements that is part of a program.
Collaboration	Working with others to develop a program; reduces bias and expands perspective.
Computational Artifact	Something created by a human using a computing device (image, audio, video, program, etc.).
Comment	Non-executed text in code that explains or documents the program for human readers.
Debugging	Finding and fixing errors (bugs) in a program.
Documentation	Written descriptions in a program that explain what the code does.
Incremental Development	Building a program in small pieces, testing each piece before adding more.
Iterative Development	Repeatedly revisiting and refining a program through multiple development cycles.
Program	A collection of program statements that performs a specific task when run by a computer.
Program Development	The full process of creating a program: designing, writing, testing, and debugging.
Prototype	An early version of a program used to test ideas before building the full solution.
Requirements	Descriptions of what a program must do; constraints that the solution must satisfy.
Testing	Running a program with various inputs to verify it behaves correctly.
User	A person who uses a program and interacts with its interface.
Modularity	Breaking a program into smaller, self-contained pieces (procedures/modules) that can be developed independently.
Procedural Abstraction	Using a named procedure to hide implementation details; you know WHAT it does, not HOW.
Expected Behavior	The output or result a program should produce for a given input, as defined by requirements.

Analog Data	Data measured on a continuous scale (e.g., sound waves, temperature).
Binary	A base-2 number system using only 0 and 1; the foundation of all digital data.
Bit	The smallest unit of digital data; a single binary digit (0 or 1).
Byte	8 bits; can represent 256 distinct values (2^8).
Clean Data	Data that has been checked and corrected for accuracy, completeness, and consistency.
Cleaning Data	The process of removing errors, inconsistencies, or irrelevant data from a dataset.
Compression	Reducing the size of data to save storage or speed up transmission.
Data	Information in a form that can be processed by a computer.
Data Set	A collection of related data, often organized in a table with rows and columns.
Digital Data	Data represented as discrete values (0s and 1s).
Filtering Data	Selecting a subset of data that meets specific criteria.
Lossless Compression	Compression that allows the original data to be perfectly reconstructed (e.g., ZIP, PNG).
Lossy Compression	Compression that permanently removes some data to achieve a smaller file size (e.g., MP3, JPEG).
Metadata	Data that describes other data (e.g., file size, creation date, author).
Overflow Error	An error that occurs when a computed value exceeds the storage capacity of its data type.
Pattern	A repeated or regular arrangement in data that can reveal trends or relationships.
Roundoff Error	An error caused by the inability to represent a decimal exactly in binary floating point.
Sampling	Collecting data from a subset of a population to represent the whole.
Structured Data	Data organized in a defined format (e.g., spreadsheet, database table).
Unstructured Data	Data without a predefined format (e.g., text documents, images, social media posts).
Visualization	Representing data graphically (charts, graphs, maps) to reveal patterns or insights.
Collaboration (Data)	Multiple groups or organizations combining datasets to enable richer analysis.
Scalability	The ability of a system to handle growing amounts of data or users.
Problem (Data)	A question or challenge that data analysis aims to answer.
Binary Representation	How all digital data — numbers, text, images, sound — is ultimately stored as 0s and 1s.
Color Representation	Colors stored as RGB triplets: three 8-bit values (0–255) for red, green, and blue channels.

AND (Logical)	A Boolean operator that returns TRUE only if both operands are TRUE.
Arithmetic Operators	Operators that perform math: +, -, *, /, MOD (remainder), and integer division.
Assignment	Setting a variable to a value using the left arrow (←) in AP pseudocode.
Boolean Expression	An expression that evaluates to TRUE or FALSE.
Boolean Value	A data type with only two possible values: TRUE or FALSE.
Calling a Procedure	Executing a named block of code (procedure/function) from another part of the program.
Concatenation	Joining two strings together end-to-end.
Conditional	A statement that executes different code based on whether a condition is TRUE or FALSE (IF/ELSE).
Decision Problem	A problem with a yes-or-no answer; some are undecidable (no algorithm can always solve them).
Element (List)	A single item in a list, accessed by its index.
FOR EACH Loop	A loop that iterates over every element in a list, one at a time.
Function / Procedure	A named, reusable block of code that performs a specific task.
Heuristic	An approach to a problem that finds a good-enough solution when an optimal one is too costly.
Index	The position of an element in a list; AP CSP lists are 1-indexed (first element = index 1).
Infinite Loop	A loop that never terminates because its exit condition is never met.
Input	Data provided to a program (keyboard, mouse, file, sensor, etc.).
Iteration	Repeating a block of code using a loop (REPEAT N TIMES or REPEAT UNTIL).
Length (List)	The number of elements in a list; accessed via LENGTH(list) in AP pseudocode.
Linear Search	Checking each element of a list one by one until the target is found; works on unsorted data.
List	An ordered, changeable collection of items; AP CSP lists are 1-indexed.
Logic Error	A mistake in the algorithm that causes wrong results without crashing the program.
MOD Operator	Returns the remainder of integer division (17 MOD 5 = 2).
Nested Conditional	An IF statement inside another IF statement, enabling more complex decision-making.
NOT (Logical)	A Boolean operator that reverses the truth value of an expression.
OR (Logical)	A Boolean operator that returns TRUE if at least one operand is TRUE.
Output	Data a program produces (display, sound, file, network, etc.).
Parameter	A variable in a procedure definition that receives a value when the procedure is called.
Return Value	The value a function sends back to the calling code after it finishes executing.
Sequencing	Statements execute in the order they appear; the most fundamental program structure.
String	A sequence of characters treated as a single value.
Syntax Error	A mistake that violates the rules of the programming language; prevents the program from running.
Traversal	Processing each element of a list, usually with a loop.
Undecidable Problem	A problem for which no algorithm can always produce a correct yes/no answer (e.g., Halting Problem).
Variable	A named storage location that holds a value which can change during program execution.
WHILE Loop (REPEAT UNTIL)	A loop that continues until a condition becomes TRUE.
Binary Search	Efficiently finds a target in a SORTED list by repeatedly halving the search space; O(log n).
Efficiency	How well an algorithm uses time and memory; measured by how runtime grows with input size.

Bandwidth	The maximum amount of data that can be transmitted over a network in a given time (bits/second).
Binary Sequence	A sequence of 0s and 1s used to represent all data in computing systems.
Bit Rate	The number of bits transmitted per second over a network connection.
Client	A device or application that requests services or resources from a server.
Cybersecurity	Practices and technologies designed to protect systems, networks, and data from attacks.
Denial of Service (DoS)	An attack that overwhelms a server with requests to make it unavailable to legitimate users.
Encryption	Converting data into a coded form so only authorized parties can read it.
Fault Tolerant	A system that continues to function even when parts of it fail.
Firewall	A security system that monitors and controls incoming/outgoing network traffic based on rules.
Hardware	The physical components of a computer (CPU, RAM, storage, keyboard, etc.).
HTTP / HTTPS	Protocols for transferring web pages; HTTPS adds encryption for security.
Information Privacy	The right to control how personal data is collected, stored, and shared.
Internet	A global network of interconnected networks communicating using standard protocols (TCP/IP).
IP Address	A unique numerical label assigned to each device on a network (e.g., 192.168.1.1).
Latency	The delay between sending a request and receiving a response over a network.
Malware	Malicious software designed to disrupt, damage, or gain unauthorized access to systems.
Network	A group of connected computing devices that can communicate and share resources.
Operating System	Software that manages hardware resources and provides services for programs.
Packet	A small unit of data sent across a network; large messages are broken into packets.
Packet Switching	A method of transmitting data by breaking it into packets that may take different routes.
Parallel Computing	Using multiple processors to solve parts of a problem simultaneously, reducing total time.
Phishing	A social engineering attack using deceptive emails or websites to steal credentials.
Protocol	A set of rules that defines how data is formatted and transmitted between devices.
Router	A networking device that forwards data packets between networks.
Server	A device or software that provides services or resources to clients on a network.
Software	Programs and operating information that tell hardware what to do.
TCP/IP	The fundamental communication protocol suite of the Internet; ensures reliable delivery.
Virus	Malware that attaches itself to legitimate programs and spreads when those programs run.
World Wide Web (WWW)	A system of interlinked hypertext documents accessed via the Internet using HTTP.
Sequential Computing	Tasks are executed one at a time in order; contrasted with parallel computing.
DNS (Domain Name System)	A system that translates human-readable domain names (e.g., google.com) into IP addresses.
Redundancy	Duplicate components in a network so that if one path fails, another can be used — key to fault tolerance.

Accessibility	Designing technology to be usable by people of all abilities, including those with disabilities.
Bias (Computing)	Systematic errors in algorithms or datasets that produce unfair or inaccurate results.
Citizen Science	Research projects where the general public contributes data or analysis.
Collaboration (Impact)	Computers enable global collaboration, allowing distributed teams to work together.
Copyright	Legal protection for original creative works; controls who can copy or distribute them.
Creative Commons	A licensing system allowing creators to share works with specific usage permissions.
Crowdsourcing	Collecting input, ideas, or data from a large group of people, often via the Internet.
Cybercrime	Criminal activity carried out using computers or the Internet.
Data Mining	Analyzing large datasets to discover patterns, correlations, or useful information.
Digital Divide	The gap between those with access to technology/Internet and those without.
Environmental Impact	The effect computing has on energy consumption, e-waste, and carbon emissions.
Ethics	A set of moral principles that guide decisions about right and wrong uses of technology.
Filter Bubble	A state of intellectual isolation caused by algorithms showing users only content they already agree with.
Intellectual Property	Creative works protected by copyright, patents, or trademarks.
Moore's Law	The observation that the number of transistors on a chip roughly doubles every two years.
Open Source	Software whose source code is freely available for anyone to view, modify, and distribute.
Personal Data	Information that can be used to identify an individual (name, email, location, etc.).
Privacy	The ability of individuals to control what personal information is shared and with whom.
Search Algorithm	An algorithm used by search engines to rank and retrieve web pages (e.g., PageRank).
Security	Measures taken to protect data and systems from unauthorized access or damage.
Surveillance	Monitoring of individuals or groups, often using computing technology.
Targeted Advertising	Using personal data to serve advertisements specifically tailored to individual users.
Terms of Service	Legal agreements users accept when using software or online services.
Unintended Consequences	Unexpected negative outcomes of a computing innovation not foreseen by its creators.
Dopamine Loop	A feedback cycle in which technology use triggers reward responses, encouraging continued engagement.
Legal Issue	Questions of law related to computing: copyright infringement, privacy violations, hacking laws.
Vishing	Voice phishing — using phone calls to trick victims into revealing personal information.
Computing Innovation	An innovation that uses a program as an integral part of its function (apps, self-driving cars, etc.).
Disinformation	False information deliberately spread to deceive; computing enables rapid large-scale distribution.
Automation	Using computers to perform tasks that previously required human effort.

Exam Tip: Big Idea 3 (Algorithms & Programming) is ~30% of the AP CSP exam — the single largest section. Big Idea 5 (Impact of Computing) is second at ~25%. Together they are more than half the exam.

Pairs perfectly with: the AP CSP Pseudocode Reference Sheet and AP CSP Complete Study Bundle — save $12 buying all three together.