ap computer science principles vocabulary to know

Abstraction

The process of reducing complexity by focusing on the main idea

Algorithm

a finite set of instructions that accomplish a specific task

Analog

Analog data have values that change smoothly, rather than in discrete intervals, over time

Argument

Specify the values of the parameters when a procedure is called

Asymmetric encryption

Uses a public key for encryption and a private key for decryption

Bandwidth

The maximum amount of data that can be sent in a fixed amount of time

Bias

In computer systems causes unfair tendencies for or against individuals or groups of individuals

Binary search

An algorithm that is often more efficient than linear search because it starts at the middle of a sorted data set and eliminates half of the data; the process repeats until a desired value is found or all elements have been eliminated. Data must be sorted in order to use this method.

Bit

Shorthand for binary digit and is either 0 or 1

Boolean

A value that is either true or false

Byte

8 bits

Certificate authorities

Entities that issue digital certificates that validate the ownership of encryption keys used in secure communications

Citizen science

Scientific research conducted in whole or part by distributed individuals, many of whom may not be scientists, who contribute relevant data to research using their own computing devices

Cleaning data

Is a process that makes the data uniform without changing their meaning (e.g., replacing all equivalent abbreviations, spellings, and capitalizations with the same word)

Computer Network

Is a group of interconnected computing devices capable of sending and receiving data (is a type of computing system)

Computer virus

Is a malicious program that can copy itself and gain access to a computer in an unauthorized way

Computing innovation

Includes a program as an integral part of its function

Computing system

Is a group of computing devices and programs working together for a common purpose

Conditional statement

("if"-statements) execute different statements based on the value of a Boolean expression

Creative commons

A public copyright license that enables the free distribution of an otherwise copyrighted work. This is used when the content creator wants to give others the right to share, use, and build upon the work they created

Crowdsourcing

Obtaining input or information from a large number of people via the Internet

Data compression

Can reduce the size (number of bits) transmitted or stored data

Decidable problem

A decision problem for which an algorithm can be written to produce a correct output for all inputs

Decision problem

A problem with a yes/no answer

Decryption

The process of decoding data that has been encrypted

Digital divide

The difference in access to computing devices and the Internet, based on socioeconomic, geographic, or demographic characteristics

Distributed computing

A computational model in which program operations are run on multiple devices

Encryption

The process of encoding data to prevent unauthorized access

Fault tolerant

The ability of a computer system to continue functioning when one or more of its devices or connections fail

Heuristic

An approach to a problem that produces a solution that is not guaranteed to be optimal but may be used when finding a guaranteed optimal solution is impractical

Iteration (for or while loop)

Is a repeating portion of an algorithm

Keylogging

The use of a program to record every keystroke made by a computer user in order to gain fraudulent access to passwords and other confidential information

Linear search

Check each element of a list, in order, until the desired value is found or all elements in the list have been checked

Logic error

Is a mistake in an algorithm or program that causes it to behave incorrectly or unexpectedly

Lossless compression

Algorithm to reduce the number of bits stored or transmitted while guaranteeing complete reconstruction of the original data

Lossy Compression

Algorithm to reduce the number of bits stored or transmitted but only allows reconstruction of an approximation of the original data

Malware

Software intended to damage a computing system or to take partial control over its operation

Metadata

Data about data. For example, for an image, it may include the date of creation or the file size of the image

Multi-factor authentication

A method of computer access control in which a user is only granted access after successfully presenting several pieces of evidence

nested conditional statements

Consist of conditional statements within conditional statements

Open Access

Online research output free of any and all restrictions on access and free of many restrictions on use, such as copyright or license restrictions

open source

Programs that are made freely available and may be redistributed and modified

Overflow Error

Is an error that occurs when a program attempts to handle data that is outside of the defined range of values

packet

A small amount of data along with some metadata used for routing it between the origin and the destination on the Internet, as well as data for reassembly

Parallel Computing

A computational model in which program operations are broken into multiple smaller sequential computing operations, some of which are performed simultaneously

Time takes as long as its sequential tasks plus the longest of its parallel tasks

Parallel systems

Multiple computing devices connected to complete many calculations or processes simultaneously

Parameter

Are input variables of a procedure (used to define the function)

Personally Identifiable Information (PII)

Information about an individual that identifies, links, relates, or describes them

Phishing

A technique that attempts to trick a user into providing personal information

Protocol

An agreed-upon set of rules that specify the behavior of a system

Internet protocols are open (everyone has access to them)

Redundancy

The inclusion of extra components that can be used to mitigate failure of a system if other components fail (helps create fault-tolerance)

Rouge Access Point

A wireless access point that gives unauthorized access to secure networks

Round-off Error

Is the difference between an approximation of a number used in computation and its exact (correct) value

Occurs when a value exceeds the range of numbers that can be represented by a fixed number of bits

Routing

The process of finding a path from the send device to receiving device

Run-time error

Is a mistake in a program that occurs during the execution of the program

Scalability

Is the capacity for a system to change in size and scale to meet new demands

Selection (if or if/else)

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

Sequencing

Is the application of each step of an algorithm in the order in which the code statements are given

Sequential computing

A computational model in which program operations are performed in order one at a time

Software library

Collection of procedures (functions) that are ready to be used in creating new programs

Speedup

The speedup of a parallel solution is measured in the time it took to complete the task sequentially divided by the time it took to complete the task in parallel

String

Is an ordered sequence of characters

String concatenation

Joins two or more strings end-to-end to make a new string

Symmetric encryption

Uses a single key for both encryption and decryption

Syntax error

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

The Internet

The world-wide computer network consisting of interconnected networks that use standardized, open (nonproprietary) communication protocols

Undecidable problem

A decision problem for which no algorithm can be constructed that is always capable of providing a correct yes-or-no answer

World Wide Web (WWW)

A system of linked pages, programs, and files shared on the internet

HTTP is a protocol used by the WWW

WWW uses the Internet