final

lossy compression

(or irreversible compression) a data compression method that uses inexact approximations, discarding some data to represent the content. Most commonly seen in image formats like .jpg.

DDoS Attack

- Distributed Denial of Service Attack. Typically a virus installed on many computers (thousands) activate at the same time and flood a target with traffic to the point the server becomes overwhelmed.

cloud computing disadvantages

1. Cloud Computing is dependent on Internet Access. 2. Documents editors are quite basic so they don't have the range of features available in commercial software. I.e. think about Microsoft Word Vs a Google Doc 3. Not good at memory heavy applications such as Video editing. These have to be done on a desktop Computer.

Hexadecimal

A base-16 number system that uses sixteen distinct symbols 0-9 and A-F to represent numbers from 0 to 15.

hexidecimal

A base-16 number system that uses sixteen distinct symbols 0-9 and A-F to represent numbers from 0 to 15.

byte

A byte is a unit of data that is 8 bits long. A byte is the standard "chunk size" for binary information in most modern computer.

bit

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

Array

A data structure in JavaScript used to represent a list.

Sub domain

A domain name under the control of a higher-level domain name.

List

A generic term for a programming data structure that holds multiple items.

Internet:

A group of computers and servers that are connected to each other.

Pair Programming

A method of programming in which two programmers write code using a single computer. One programmer in the "driver" role uses the mouse and keyboard to actually write the code while a second acts as a "navigator", keeping track of the big picture, catching errors, and making suggestions. Programmers switch roles frequently and communicate throughout the process.

Function

A named group of programming instructions. Functions are reusable abstractions that reduce the complexity of writing and maintaining programs.

innovation

A new or improved idea, device, product, etc, or the development thereof

IP Address:

A number assigned to any item that is connected to the Internet.

Variable

A placeholder for a piece of information that can change.

algorithm

A precise sequence of instructions for processes that can be executed by a computer

Low Level Programming Language

A programming language that captures only the most primitive operations available to a machine. Anything that a computer can do can be represented with combinations of low level commands.

High Level Programming Language

A programming language with many commands and features designed to make common tasks easier to program. Any high level functionality is encapsulated as combinations of low level commands.

Protocol

A set of rules governing the exchange or transmission of data between devices.

Protocol:

A set of rules governing the exchange or transmission of data between devices.

protocol

A set of rules governing the exchange or transmission of data between devices.

Boolean

A single value of either TRUE or FALSE

Router:

A type of computer that forwards data across a network

image

A type of data used for graphics or pictures.

Global Variable

A variable whose scope is "global" to the program, it can be used and updated by any part of the code. Its global scope is typically derived from the variable being declared (created) outside of any function, object, or method.

binary

A way of representing information using only two options.

Data Type

All values in a programming language have a "type" - such as a Number, Boolean, or String - that dictates how the computer will interpret it. For example 7+5 is interpreted differently from "7"+"5"

ACII

American Standard Code for Information Interchange; the universally recognized raw text format that any computer can understand

Event

An action that causes something to happen.

URL

An easy-to-remember address for calling a web page (like www.code.org).

SSL/TLS - Secure Sockets layer / Transport Layer Security

An encryption layer of HTTP that uses public key cryptography to establish a secure connection.

parameter

An extra piece of information passed to a function to customize it for a specific need

==

The equality operator (sometimes read: "equal equal") is used to compare two values, and returns a Boolean (true/false). Avoid confusion with the assignment operator "=",

Debugging

Finding and fixing problems in an algorithm or program.

HTTP

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

Private Key

In an asymmetric encryption scheme the decryption key is kept private and never shared, so only the intended recipient has the ability to decrypt a message that has been encrypted with a public key.

IETF

Internet Engineering Task Force - develops and promotes voluntary Internet standards and protocols, in particular the standards that comprise the Internet protocol suite (TCP/IP).

If-Statement

The common programming structure that implements "conditional statements".

for loop

Loops that have a predetermined beginning, end, and increment (step interval).

Sequencing

Putting commands in correct order so computers can read the commands.

Packets:

Small chunks of information that have been carefully formed from larger chunks of information.

loop

The action of doing something over and over again.

DNS

The service that translates URLs to IP addresses.

User Interface

The visual elements of a program through which a user controls or communicates with the application. Often abbreviated UI.

latency

Time it takes for a bit to travel from its sender to its receiver.

Iterate

To repeat in order to achieve, or get closer to, a desired goal.

Iterate

To repeat in order to achieve, or get closer to, a desired goal. Selection - A generic term for a type of programming statement (usually an if-statement) that uses a Boolean condition to determine, or select, whether or not to run a certain block of statements.

TCP

Transmission Control Protocol - provides reliable, ordered, and error-checked delivery of a stream of packets on the internet. TCP is tightly linked with IP and usually seen as TCP/IP in writing.

Public Key Encryption

Used prevalently on the web, it allows for secure messages to be sent between parties without having to agree on, or share, a secret key. It uses an asymmetric encryption scheme in which the encryption key is made public, but the decryption key is kept private.

Cracking encryption

When you attempt to decode a secret message without knowing all the specifics of the cipher, you are trying to "crack" the encryption. Decryption - a process that reverses encryption, taking a secret message and reproducing the original plain text

Computationally Hard

a "hard' problem for a computer is one in which it cannot arrive at a solution in a reasonable amount of time

big data

a broad term for datasets so large or complex that traditional data processing applications are inadequate.

Turtle Programming

a classic method for learning programming with commands to control movement and drawing of an on-screen robot called a "turtle". The turtle hearkens back to early implementations in which children programmed a physical robot whose dome-like shape was reminiscent of a turtle.

Library

a collection of commands / functions, typically with a shared purpose

API

a collection of commands made available to a programmer

lossless

a data compression algorithm that allows the original data to be perfectly reconstructed from the compressed data.

Documentation

a description of the behavior of a command, function, library, API, etc.

Callback function

a function specified as part of an event listener; it is written by the programmer but called by the system as the result of an event trigger.

modulo

a mathematical operation that returns the remainder after integer division. Example: 7 MOD 4 = 3

Moore's Law

a prediction made by Gordon Moore in 1965 that computing power will double every 1.5-2 years, it has remained more or less true ever since.

Heurisitics

a problem solving approach (algorithm) to find a satisfactory solution where finding the best or exact solution is impractical or impossible.

Top Down Design

a problem solving approach (also known as stepwise design) in which you break down a system to gain insight into the sub-systems that make it up.

Encryption

a process of encoding messages to keep them secret, so only "authorized" parties can read it.

Event-driven program

a program designed to run blocks of code or functions

Event-driven program

a program designed to run blocks of code or functions in response to specified events (e.g. a mouse click)

Virus

a program that runs on a computer to do something the owner of the computer does not intend.

Models and Simulations

a program which replicates or mimics key features of a real world event in order to investigate its behavior without the cost, time, or danger of running an experiment in real life

while loop

a programming construct used to repeat a set of commands (loop) as long as (while) a boolean condition is true.

Abstraction

a simplified representation of something more complex. Abstractions allow you to hide details to help you manage complexity, focus on relevant concepts, and reason about problems at a higher level.

abstraction

a simplified representation of something more complex. Abstractions allow you to hide details to help you manage complexity, focus on relevant concepts, and reason about problems at a higher level.

Caesar Cipher

a technique for encryption that shifts the alphabet by some number of characters

Phishing Scam

a thief trying to trick you into sending them sensitive information. Typically these include emails about system updates asking you send your username and password, social security number or other things.

symmetric encryption

an encryption scheme in which the key used to encrypt data is also used to decrypt (contrast with: asymmetric encryption)

Random Substitution Cipher

an encryption technique that maps each letter of the alphabet to a randomly chosen other letters of the alphabet.

asymmetric means

different keys are used to encrypt and decrypt a message (public and private)- anyone can send encrypted messages but she is the only one that can decode them with her private key

cloud computing advantages

example of cloud computing - google docs - 1. create documents 2. save online 3. access anywhere 4. share with others 5. Collaborate (work with other person at the same time from different devices) on a document

Network Redundancy:

having multiple backups to ensure reliability during cases of high usage or failure

Boolean Expression

in programming, an expression that evaluates to True or False.

metadata

is data that describes other data. For example, a digital image may include metadata that describe the size of the image, number of colors, or resolution.

selection

making choices (if x is less then four)

UI Elements

on-screen objects, like buttons, images, text boxes, pull down menus, screens and so on.

pixel

short for "picture element", the fundamental unit of a digital image, typically a tiny square or dot that contains a single point of color of a larger image.

Firewall

software that runs on servers (often routers) that only allows traffic through according to some set of security rules.

bit rate

sometimes written bitrate) the number of bits that are conveyed or processed per unit of time. e.g. 8 bits/sec.

RGB

the RGB color model uses varying intensities of (R)ed, (G)reen, and (B)lue light are added together in to reproduce a broad array of colors.

Cipher

the generic term for a technique (or algorithm) that performs encryption

Cloud Computing

the practice of using a network of remote servers hosted on the Internet to store, manage, and process data, rather than a local server or a personal computer.

Net Neutrality:

the principle that all Internet traffic should be treated equally by Internet Service Providers.

net neutrality

the principle that all Internet traffic should be treated equally by Internet Service Providers.

asymmetric encryption

used in public key encryption, it is scheme in which the key to encrypt data is different from the key to decrypt.

Antivirus Software

usually keeps big lists of known viruses and scans your computer looking for the virus programs in order to get rid of them.