AP Computer Science Principles Flashcards

Flashcards for AP Computer Science Principles exam review.

Creative Development

process of designing, building, and refining a computer program — from the original idea to the final product.

User Interface

A User Interface is how a person interacts with a computer program or system.

It includes everything the user sees, touches, or clicks to give input or get output.

Input

Data that is sent to a computer for processing.

Output

Data sent from a program to a device.

Program

A program is a set of instructions written by a programmer that a computer can follow to do a specific task.

Think of it like a recipe:

• You give the computer steps to follow

• It runs those steps in order to produce output

Program Event

An action that happens in a program (like a user action) that triggers code to run.

Event Driven Program

A program that waits for something to happen, like a click or key press, and responds to it.

Sequential Program

Happens in order

Iterative Development Process

It's when you build a working version of your program, test it, and then go back and improve or fix it — over and over.

• You go through the cycle of:

  1. Plan

  2. Code

  3. Test

  4. Fix or improve

  5. Repeat!

Incremental development process

Programmers break the program they are working on into smaller pieces and make sure that each piece works before adding it to the whole

Program Documentation

A description of how something in your program works.

Syntax Error

spelling and/or punctuation rules of the programming language aren't followed

Logic Error

A logic error is when your program runs without crashing, but the output is wrong because there’s a mistake in how you wrote the logic.

It’s not a bug that crashes — it’s a wrong answer!

Your code works syntactically (no red error), but you told it to do the wrong thing

Run-Time Error

An error that occurs when the program is running.

Overflow Error

An error that occurs when a computer tries to handle a number that’s outside of its defined range of values

Debugging

The process of finding and fixing errors.

Data

Collection of facts

Number base

The number of digits or digit combos that a system uses to represent values

Bit

Smallest unit of info stored or manipulated on a computer (0/1)

Byte

8 bits form this

Analog Data

Data that is measured continuously

Sampling

you’re taking small bits of a bigger thing to understand or represent the whole.

Data Abstraction

Data abstraction means organizing complex data into simpler, more manageable parts so it’s easier to work with.

It’s like hiding details you don’t need so you can focus on what matters.

Data Compression

Set of steps of packing data into a smaller space while allowing for the original data to be seen

Run Length Encoding

RLE compresses data by replacing repeated values with a count and the value itself.

AAAAABBCCCCD

5A2B4C1D

Lossless Data Compression

Allows you to reduce your file size without sacrificing any of the original data in the process

Lossy Data Compression

Sacrifices some data in order to achieve greater compression

Big Data

Large data sets

Metadata

Data about data

Data Mining

Data mining = analyzing large data sets to find patterns or useful info — like predicting what you’ll click or buy.

Data Transformation

It means changing, filtering, or re-organizing data to make it more useful or easier to understand.

Bar-Chart

A chart or graph that presents categorical data with rectangular bars with heights or lengths proportional to the values that they represents

Scatter Plots

Uses dots to represent values for two different numeric variables

Line graphs

Uses lines to represent the values

Variable

A placeholder in your program for a value. It’s usually represented by letters or words.

Global Variable

Can be used anywhere. Is used outside of an event

Local variable

Used only in part of the code it was created, deleted once onevent is done. Variable is inside an event

Data Types

Data types are the kinds of information a program can work with.

They tell the computer how to store and handle the data.

Data Type	What It Is	Example
Number	Any numeric value	5, -10, 3.14
Boolean	True or false	true, false
String	Text in quotes	"hello", "123"
List	A group of items	[1, 2, 3], ["a", "b"]
Variable	A named container that stores data	score = 7, name = "Bob"

Substring

A substring is a part of a string — just a smaller piece of the whole text.

List

An ordered sequence of elements. They are also known as arrays

Boolean

Can only represent two values: true or false : computers use this to make decisions inside conditionals (if then)

Nested Conditionals

Conditional statements inside conditional statements

Element

An individual value in a list

Data Abstraction

Simplifies a set of data by representing it in some general way

Linear Search

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

Binary Search

Starts in the middle of a sorted data set and eliminates half of the data based on what it’s looking for. It repeats the process until the desired value is found.

Procedure

A group of programming instructions. They are also called methods or functions

Parameters

The input variables of a procedure

Arguments

An argument is the actual input you send into a procedure — it replaces the parameter when the procedure runs. Its the input the user provides.

Procedural Abstraction

It's when you break a big problem into smaller parts using procedures (also called functions or methods).

Algorithm

A set of instructions used to accomplish a specific task or solve a problem

Sequencing

Consists of steps that go in order

Selection

If/ else

Iteration

Refers to the repetition of a set of instructions until a specific condition is met. It allows programs to perform tasks repeatedly without having to write repetitive code

Infinite Loops

Are loops that continue to repeat indefinitely because the condition controlling the loop is always true or there is no condition at all

MOD operator

A is divided by b and MOD gives you what the remainder would be

Simulations

The process of creating a model or representation of a real world system or phenomenon on a computer. Simulations are an example of abstraction

Problem

A problem is a general task you want an algorithm to solve.

Decision Problems

Yes or no answer

Optimization Problem

Wants the best answer! Ex) shortest path of a route

Undecidable Problem

If an algorithm can’t be written that’s always capable of providing a correct yes or no answer

Internet

A computer network consisting of interconnected networks that use standardized, open (NONPROPRIETARY) communication protocols

Computing Device

A physical machine that can run a program

Computing Network

A computing network is a group of connected devices that can send and receive data.

It’s how computers "talk" to each other.

Each device on the network is called a node — and they can:

• Share files

• Access the internet

• Send messages or data

Home Wi-Fi Your phone, laptop, TV connected wirelessly

Computing System

A computing system is a group of computing devices and programs that work together to perform tasks or solve problems.

Your smartphone is a computing system:

• You type on the screen (input)

• It runs an app (program)

• It uses GPS and camera (hardware)

• It connects to the internet (network)

All of those parts are working together — that’s a computing system.

Packets

A packet is a small chunk of data sent across a network.

When you send something big (like a file, image, or video), it’s too large to send all at once — so it's broken into packets.

Paths

A path is the route that data packets take to travel from one computing device to another across the internet or a network.

Routing

The process of finding a path to take

Bandwidth

the rate of data transfer it allows from one device to another

Latency

How late the bits arrive

Protocol

A standard set of rules that everyone agrees on. They are OPEN or NONPROPRIETARY.

TCP/IP

• TCP = ensures data is reliable & ordered

• IP = gets data to the right place

• Packets may arrive out of order or missing — TCP fixes this

UDP

Offers a way to deliver a faster stream of information by eliminating error checking which TCP/IP does.

World Wide Web

A system of web pages, programs and files

HTTP

A Hypertext transfer protocol which controls how web page data is transmitted (enables communication between web browsers)

Scalability

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

Fault tolerance

It can function properly even in the event of one part failing

Redundancy

The inclusion of extra components that can be used to mitigate failure of a system of other components fail

Parallel Computing

A program is broken into smaller sequential computing operations using multiple PROCESSORS

Sequential Computing

Traditional method of executing instructions in a sequential order

Distributed Computing

Multiple DEVICES are used to run a program : allows users to share information

Digital Divide

Refers to the gaps between those who have access to technology and the internet and those who don’t

Biases

Tendencies or inclinations, especially those that are unfair or prejudicial

Machine Learning Models

Computer programs that can learn from data and make predictions or decisions without being programmed

Citizen Science

Scientific research that the general population helps to conduct. Ordinary citizens help contribute data to research projects using computing devices

Crowdsourcing

The practice of getting a large amount of input or information from people on the internet

Intellectual Property

The creations of the mind such as inventions, literary and artistic works, designs and images used in commerce

Public Domain

These are creative works that are free to use without permission

Copyright

The legal right that the creator of a work has to it

Plagiarism

When you take the content of someone else and claim it as your own

Creative Commons

A public copyright license that creators use when they want to GIVE others the right to use their work

Fair Use

Fair use is a legal rule that lets you use someone else’s copyrighted work without permission — but only in limited situations.

Letter	Stands for	What It Means
P	Purpose	Is it for education, news, or parody — not profit?
A	Amount	Are you using only a small part of the work?
N	Nature	Is the original work factual (more okay) or creative?
E	Effect	Will your use hurt the market value of the original?

Open Sourcing

Allows for work to be freely distributed, and modified

Open Access

Free-to-use research or data with no paywalls or copyright barriers — often created for the public good.

Targeted Marketing

Engines can track your search history and use it to suggest websites and ads

Personally Identifiable Information

This is the information that can be used to identify you

Virus

A malicious program that can gain unauthorized access to something and copy itself. It must be activated by the user.

Worms

Can operate independently

Computer Viruses

Type of malware or malicious software that is intended to damage.

Security Patch

Update to app and fixes bugs