Definitions Flashcards
256
This is 2 to the 8th power. It is the number of different numbers that you can store in a byte (8 bits), usually ranging from 0 to 255. An 8 bit number can be represented by two hexadecimal digits or three octal digits.
AI
Artificial Intelligence
ASCII
Stands for the American Standard Code for Information Interchange. It is a 7bit code for characters. For example: the letter ’x’ is represented as 1111000. Because it is only 7 bits long, an ASCII character can be stored in a byte.
Abstraction
Removing detail of something to focus on a subset of the features without confusing details.
Address
a) A location in memory or identifying a particular piece of memory.
b) An identification that allows access to something such as an internet address which allows one to access a device on the internet.
Agent Based Modeling
A method of simulating the real world in which individual agents interact with their environment and each other to simulate real world behaviors and conditions. NetLogo is good at Agent Based Modeling.
Agent
Independent acting sections of code and data that represent active interacting pieces of a model or system.
Algorithm
A set of instructions for accomplishing a task that when executed will terminate.
Analog
Measured in continuous values. The audio signal from a microphone is analog. A clock with hands is considered analog.
Application
A runnable program that provides some service.
Argument
One of the pieces of data provided as input to a procedure or function through the call to the procedure or function.
Artificial Intelligence
The subfield of computer science that involves the creation of programs that attempt to do what was formerly believed to only be able to be done by humans.
Assignment
This stores a value in a variable. An assignment statement has an assignment in it describing the storage of values in variables.
Autonomous
Controlled by computer programs and not people.
Bandwidth
Refers to the volume of information that can be transmitted or processed. It is usually measured in bits or bytes per time unit like “bits per second”.
Big Data
The problem beginning in the 21st century of processing vast amounts of data coming at or refreshing at very high speed. For example satellite sensor data, city monitoring sensors, gene sequencing data, etc.
Binary
The base 2 number system. Integer can be encoded as binary which is a string of 0’s and 1’s. Binary is a place-value system in which each bit position denotes a power of 2 (unlike decimal which uses 10 symbols and powers of 10). k bits of information can represent 2k different numbers. For example counting in 3 bits of binary you can count from 0 to 7: 000, 001, 010, 011, 100, 101, 110, 111.
Bit
A binary digit. The smallest unit of information represented by one of two states (usually 0 or 1). It is often denoted by a lower case ’b’ as in Mbs (mega-bits per second). Or the amount of information gained when answering a yes or no question.
Block
A collection of statements that can be grouped together to be treated as one statement. For instance in C and Processing statements inside parentheses are treated as one statement that is either executed together or not. Generally the only “entry” into a block of code is at the top of the code.
Boolean
A type in many programming languages that can hold either a True or a False. The name comes from the mathematician George Boole. It can also refer to the type of expression for example the type of the expression x > 6 is Boolean.
Boot Program
The program run when the computer hardware is powered up.
Boot
To restart a computer as if the computer had been powered down regardless of whether it was on and running or not.
Broadcast
In messaging passing it is to send the same message to all who can listen as opposed to peer-to-peer communication for instance.
Bus
a) the main path for bits traveling in parallel in and out of a CPU or between major computational, storage, and device components. It is often many bits wide.
b) Any pathway for bits to travel in parallel.
Byte
8 bits. It is often denoted by a capital B as in MB (mega-bytes).
Call
A statement in a language that starts or invokes a procedure or function.
CPU
Central Processing Unit. Where the computer instructions are executed. It usually refers to the general purpose processor that handles a range of processing tasks.
CPU intensive
A program that spends most of its time running on the CPU with a disproportionately small amount of time waiting for data from memory.
Cache
Is memory used to speed memory access, that stores data that is anticipated to be used next or was just used and may be used again. For example: cache may exist on slow physically rotating discs to save information of data that is near to the data just accessed or to hold data without writing it to disc until it is likely not to change again.
Card
A circuit board which can be plugged into your computer motherboard.
Central Processing Unit
Processing unit that takes streams of bits as data and instructions and executes the instructions on the data yielding more data and possibly instructions.
Character
A single letter or symbol that is represented by a small set of bytes in the computer. See ASCII and Unicode.
Chip
A integrated electronic circuit generally with from thousands to billions of components such as transistors and capacitors that perform complex functionality such as addressable memory, CPU, I/O functions.
Clock
The internal “drummer” or heartbeat that keeps the CPU activities across the chip and across the motherboard in sync. Often measured in megahertz or gigahertz.
Cloud Computing
Rather than computation occurring “locally” on one’s own computer, the computation is on distant machines accessible via the internet.
Cloud Storage
Rather than the information being stored “locally” on one’s own computer, the information is stored on distant machines accessible via the internet.
Cloud
a) In the phrase “in the cloud” refers to information being stored not on one’s own computer but on a distant mass storage device accessible via the internet.
b) Computing that is done not on one’s own computer but on computers accessed via the internet.
Cluster Computer
Also known as a cluster is a supercomputer made up of many smaller computers such as PCs connected with very fast network hardware.
Comment
Comments are important in programs as they are nonexecuting code that explains to a reader of the code in plain text what is going on
Comparison
This is an operation that compares things like if the values in two variables are equal. In processing the equals comparison is done with the double equals: ==. In NetLogo it is done with a single equals: =. Other comparisons are things like not equal and greater than.
Compile Time
During the time that a program is being compiled.
Compiler
A program for translating a program written in one language into code that can be executed.
Computer science
a) the study of process, data and computation.
b) A very cool profession. (No bias here. ;-) ).
Computer
An electronic device for storing and processing information based on programs stored in the computer.
Conditional
A control structure such as an if-statement or case-statement that conditionally executes a block of code
Control structure
Code or statement that changes the order of execution for instance an if-statement conditionally executes code while a loop may perform a section of code repeatedly.
Core
A sub-processor on a chip. Usually used when there are more than one processor on a single chip. Modern CPU chips often have several cores.
Customer Base
The set of loyal customers a company or other software supplier supports.
Data Abstraction
Giving a name to a complex set of data that forms a single concept thereby removing the need to always refer to all the detail. To hide the details of data by referring to the whole rather than the parts. For example a complex data structure may be necessary to describe all the details of a car but could collectively be referred to as simply the car type. All the data of the car could for instance be created, copied, sorted, deleted without mentioning all the component parts.
Data Mining
Using algorithms to infer complex results for masses of data such as sensor data or the world’s web pages. Generally to be data mining most of the data available is not relevant but large enough amounts are that it is nontrivial to draw conclusions.
Data intensive
A program that spends most of its time waiting for data from memory rather than computing. Sometimes called memory intensive.
Database
An organized collection of data and services to access them in a variety of ways relevant to the data.
Declaration
A statement in a program that attaches a property to a symbol. For example in Processing you might say: “float x” which means that the variable x has the property that it is a floating point number. In processing you have to declare variables giving them a type before you use them.
Device
A unit or piece of hardware with a specific purpose such as a disk, keyboard, audio board, etc.
Digital Divide
The societal advantages for those with internet or computer access over those who do not have access or have limited access
Digital
Measured in a set of discrete steps. The audio signal on a CD or in an mp4 file is digital. cf. Analog.
Disk
A magnetic storage device that records data on a spinning disk. The bulk of long term storage on a today’s computers is “on the disk”. The main file system is usually found here. Compare with the term SSD
Drone
An unmanned flying vehicle. May be remote controlled or autonomous.
Embedded
A computer is said to be embedded if it is integrated into the function of a physical item. The computers in a car are embedded in the car. One speaks of embedded systems.
Emacs
A classic highly reconfigurable editor that challenges vi for dominance of UNIX based text editing.
Encryption
To use a code to render data unintelligible. An encryption key is data that when supplied to an encryption program and the original data to be encrypted yields the encrypted data. A decryption key when supplied with a decryption program and encrypted data the recovers the original data. Many times these two keys are the same.
Executable
A file that can be executed by the operating system.
Expression
Is a language construct that can be used to produce a value. For example sqrt(3) or 4+7*88.
External hard drive
A disk that is a peripheral.
File Extension
When naming a file there is often a part after the last period in the file name called the file extension that indicates the type of the file such as pdf, jpg, txt, etc.
File
A single block of information allocated by an operating system for retention beyond the execution time of any program.
File System
A formatting of memory such as a disk by the Operating System to organize that memory into a hierarchy of directories and files. It can mean the format standard or the formatted memory.
Flag
A term used in reference to a Boolean variable used to answer an true or false question. For example. For example: the variable errorFlg is used in the program to indicate if an error has been found. Often flag variables are used as a parameter to control some aspect of a function or program. For example: the variable noOutput is used to control if the program is to produce any visible output or not.
Floating Point Number
A number with a decimal in it like 3.141592653589.
Front-side Bus
It is a connection between the CPU and fast components of your computer like RAM and GPU (See the term Bus). Technically it is a term for a specific Intel transport mechanism but can be used in this general way
Functional Abstraction
Abstraction to what a section of code will do rather that the details of how it does it. A function definition allows for abstracting the contained code to a simple call to a function.
Function
A standalone segment of code with a clear set of inputs and output that performs a specific function and returns a value. It is essentially a procedure that returns a value.
Giga
A prefix for a billion, (10^9) as in a gigabyte or gigahertz or gigabananas (billion bananas).
GPU - Graphics Processing Unit
It is a CPU that processes instructions specifically targeted at graphics processing. It is highly parallel with hundreds to thousands of simple cores.
Grammar
The formal specification of the syntax of a language
