Fundamentals of Data Representation and Computing Concepts

Binary

A way of representing information using only two options.

Decimal

A way of representing information using ten options.

Bit

A contraction of 'Binary Digit'; the single unit of information in a computer, typically represented as a 0 or 1.

Byte

8 bits.

Overflow Error

Error from attempting to represent a number that is too large.

Round-off Error

Error from attempting to represent a number that is too precise. The value is rounded.

Analog Data

Data with values that change continuously, or smoothly, over time.

Digital Data

Data that changes discretely through a finite set of possible values.

Sampling

A process for creating a digital representation of analog data by measuring the analog data at regular intervals called samples.

Lossless Compression

A process for reducing the number of bits needed to represent something without losing any information. This process is reversible.

Lossy Compression

A process for reducing the number of bits needed to represent something in which some information is lost or thrown away. This process is not reversible.

Intellectual Property

A work or invention that is the result of creativity, such as a piece of writing or a design, to which one has rights and for which one may apply for a patent, copyright, trademark, etc.

Creative Commons

A collection of public copyright licenses that enable the free distribution of an otherwise copyrighted work, used when an author wants to give people the right to share, use, and build upon a work that they have created.

Computing Device

A machine that can run a program, including computers, tablets, servers, routers, and smart sensors.

Computing System

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

Computing Network

A group of interconnected computing devices capable of sending or receiving data.

Path

The series of connections between computing devices on a network starting with a sender and ending with a receiver.

Bandwidth

The maximum amount of data that can be sent in a fixed amount of time, usually measured in bits per second.

Protocol

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

IP Address

The unique number assigned to each device on the Internet.

Internet Protocol (IP)

A protocol for sending data across the Internet that assigns unique numbers (IP addresses) to each connected device.

Router

A type of computer that forwards data across a network.

Packet

A chunk of data sent over a network. Larger messages are divided into packets that may arrive at the destination in order, out of order, or not at all.

Redundancy

The inclusion of extra components so that a system can continue to work even if individual components fail, for example by having more than one path between any two connected devices in a network.

Fault Tolerant

Can continue to function even in the event of individual component failures.

HTTP

HyperText Transfer Protocol - the protocol used for transmitting web pages over the Internet.

Domain Name System (DNS)

The system responsible for translating domain names like example.com into IP addresses.

Internet

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

World Wide Web

A system of linked pages, programs, and files.

Digital Divide

Differing access to computing devices and the Internet, based on socioeconomic, geographic, or demographic characteristics.

User Interface

The inputs and outputs that allow a user to interact with a piece of software.

User Interface

Can include a variety of forms such as buttons, menus, images, text, and graphics.

Input

Data that are sent to a computer for processing by a program.

Output

Any data that is sent from a program to a device.

Program Statement

A command or instruction, sometimes also referred to as a code statement.

Program

A collection of program statements that run one command at a time.

Sequential Programming

Program statements run in order, from top to bottom.

Event-Driven Programming

Some program statements run when triggered by an event, like a mouse click or a key press.

Documentation

A written description of how a command or piece of code works or was developed.

Comment

A form of program documentation written into the program to be read by people and which do not affect how a program runs.

Pair Programming

A collaborative programming style in which two programmers switch between the roles of writing code and tracking or planning high-level progress.

Debugging

Finding and fixing problems in an algorithm or program.

Development Process

The steps or phases used to create a piece of software, including investigating, designing, prototyping, and testing.

Event

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

Expression

A combination of operators and values that evaluates to a single value.

Assignment Operator

Allows a program to change the value represented by a variable.

Variable

A named reference to a value that can be used repeatedly throughout a program.

String

An ordered sequence of characters.

Boolean Value

A data type that is either true or false.

Comparison Operators

Logical Operator

NOT, AND, and OR, which evaluate to a Boolean value.

Conditional Statement

Affects the sequential flow of control by executing different statements based on the value of a Boolean expression.

Function

A named group of programming instructions, also referred to as a 'procedure'.

Function Call

A command that executes the code within a function.

Metadata

Data about data.

Citizen Science

Scientific research conducted by distributed individuals who contribute relevant data using their own computing devices.

Cleaning Data

A process that makes the data uniform without changing its meaning.

Correlation

A relationship between two pieces of data, typically referring to the amount that one varies about the other.

Crowdsourcing

The practice of obtaining input or information from a large number of people via the Internet.

Information

The collection of facts and patterns extracted from data.

Data Bias

Data that does not accurately reflect the full population or phenomenon being studied.

Data Filtering

Choosing a smaller subset of a data set to use for analysis.

List

An ordered collection of elements.

Element

An individual value in a list that is assigned a unique index.

Index

A common method for referencing the elements in a list or string using numbers.

Iteration

A repetitive portion of an algorithm that repeats a specified number of times or until a given condition is met.

Infinite Loop

Occurs when the ending condition will never evaluate to true.

Traversal

The process of accessing each item in a list one at a time.

Data Abstraction

Manage complexity in programs by giving a collection of data a name without referencing the specific details of the representation.