AP Computer Science Principles Vocabulary

Study for the AP Exam

Computing Innovation

Includes a program as an integral part of its function, can be physical, non-physical software, or non-physical concepts.

Collaboration

Includes diverse perspectives which helps avoid bias.

Strong Password

Easy for a user to remember but difficult for someone else to guess.

Algorithm

A finite set of instructions that accomplishes a specific task.

Abstraction

The process of reducing complexity by focusing on the main idea and hiding irrelevant details.

Sequencing

The application of each step of an algorithm in the given order.

Selection

Determines which parts of an algorithm are executed based on a true or false condition.

Iteration

A repeating portion of an algorithm that has a specified number of repetitions or a condition.

Encryption

The process of encoding messages to keep them secret.

Decryption

Reverses encryption by reproducing the original plain text.

Programming Language

Provides the standards, syntax, statements, and instructions for writing software.

Problem

A general description of a task that can be solved algorithmically.

Instance of a Problem

A specific task needing to be solved with specific input.

Decision Problem

A problem with a yes/no answer.

Optimization Problem

A problem that finds the best solution among many.

Decidable Problem

A decision problem with an algorithm that produces a correct output for all inputs.

Undecidable Problem

A problem for which no algorithm can consistently give a correct yes/no answer.

Scalability

The capacity of a system to change in size and scale to meet new demands.

Efficiency

An estimation of the computational resources used by an algorithm.

Linear or Sequential Search

Search algorithms that check each element of a list in order.

Binary Search

A search algorithm that starts at the middle and removes half the data.

Heuristic

An approach that produces a solution not guaranteed to be optimal.

Algorithmic Bias

Bias embedded in algorithms and software development.

Pair Programming

A collaborative style where two programmers share roles in coding.

Program

A collection of statements that performs a specific task when run.

Code Segment

A part of a program that consists of a collection of program statements.

Behavior of a Program

How a program functions during execution.

Event

Associated with an action and supplies input data to a program.

Program Documentation

Written descriptions of a code segment, event, or program.

Comments

Program documentation intended for human readers that does not affect execution.

Iterative Development Process

A process that requires refinement based on feedback.

Incremental Development Process

A process that breaks problems into smaller pieces to ensure each works.

Program Inputs

Data sent to a computer for processing by a program.

Program Outputs

Data sent from a program to a device.

Variable

An abstraction that can hold a value within a program.

Conditional Statements

Code statements that affect flow by executing based on a Boolean expression.

Boolean Value

A data type representing true or false.

Nested Conditional Statements

Conditional statements within other conditional statements.

Iteration Statements

Code statements that repeat a set of statements until a condition is met.

Procedure

A named group of programming instructions possibly with parameters.

Parameters

Input variables of a procedure.

Arguments

Specify the values of parameters when a procedure is called.

Bit

The single unit of information in a computer, represented as 0 or 1.

Byte

8 bits.

Number Bases

The different digits or combinations used in counting systems.

Binary (Base 2)

Uses only the digits zero and one.

Decimal (Base 10)

Uses the digits 0-9.

Modulus Operator

Arithmetic operator that returns the remainder of a division operation.

Round-off Error

Error caused by fixed bits representing real numbers.

List

An ordered sequence of elements.

Element

An individual value in a list with a unique index.

Index

Method for referencing elements in a list using natural numbers.

Complete List Traversal

Accessing all elements in a list.

Partial List Traversal

Accessing only a portion of elements in a list.

Logic Error

A mistake in an algorithm or program that causes incorrect behavior.

Syntax Error

A mistake in a program where the rules of the programming language are not followed.

Run-Time Error

An error that occurs during the execution of a program.

Overflow Error

Error that occurs when there are not enough bits to represent a number.

String

A sequence of characters.

Substring

A part of an existing string.

String Concatenation

Joins two or more strings to create a new string.

Application Program Interface (API)

Specifications for how library procedures behave and can be used.

Data Abstraction

Separates abstract properties of a data type from its details.

Procedural Abstraction

Provides a name for a process to use without knowing how it works.

Modularity

Subdivision of a program into separate subprograms.

Analog Data

Values that change smoothly over time.

Sampling Technique

Technique used to measure values of an analog signal.

Data Compression

Method to reduce the size of transmitted or stored data.

Lossless Data Compression

Compression that allows complete reconstruction of original data.

Lossy Data Compression

Compression that allows reconstruction of an approximation of original data.

Creative Commons

A public copyright license enabling free distribution of copyrighted work.

Open Source

Programs made freely available for redistribution and modification.

Open Access

Online research output free of access restrictions.

Information

Collection of facts and patterns extracted from data.

Cleaning Data

Process that makes data uniform without changing its meaning.

Citizen Science

Scientific research conducted by non-scientists contributing data.

Crowdsourcing

Obtaining input from a large number of people via the Internet.

Simulation

Representation using varying values to reflect changes in a phenomenon.

Personally Identifiable Information (PII)

Information that identifies or describes an individual.

Metadata

Data about data.

Digital Divide

Differing access to computing devices based on characteristics.

Computing Device

A physical device that can run a program.

Computing System

A group of devices and programs working together.

Computer Network

Interconnected devices capable of data transmission.

Redundancy

Inclusion of extra components to mitigate failure.

Fault-Tolerant

A system that continues to function despite failures.

Protocol

Agreed-upon rules that specify system behavior.

Bandwidth

Maximum data that can be sent in a fixed time.

Routing

Finding a path from sender to receiver.

Path

A sequence of directly connected computing devices.

Data Streams

Streams containing chunks of data encapsulated in packets.

Packets

Data chunks containing data and metadata for routing.

World Wide Web

A system of linked pages, programs, and files.

HTTP

A protocol used by the World Wide Web.

Sequential Computing

Computational model with operations performed in order.

Distributed Computing

Computational model using multiple devices.

Parallel Computing

Computational model with multiple operations performed simultaneously.

Speedup of a Parallel Solution

Time taken for a task sequentially divided by time taken in parallel.

Public Key Encryption

Encryption using a public and a private key.

Multifactor Authentication

Access control method requiring multiple evidence pieces for authentication.