key terms

Question 1

computational thinking

Answer 1

a problem-solving approach that includes abstraction, decomposition, and algorithm development

Question 2

decomposition

Answer 2

breaking down a problem into smaller parts that are easier to solve.

Question 3

object oriented programming

Answer 3

a program made up of objects, each object contains methods (functions) and attributes (variables)

Question 4

instruction set

Answer 4

the collection of opcode a processor is able to decode and execute

Question 5

pipelining

Answer 5

where the output of one process is the input to another

Question 6

data mining

Answer 6

can show patterns and relationships that aren’t obvious but can be find through pattern matching large quantities of data

Question 7

caching

Answer 7

data is stored in the cache in case uts needed again soon, so it doesn’t need to be refetched from the RAM

Question 8

prefetching

Answer 8

when an instruction is requested from memory by the CPU before its required to speed up instruction throughput

Question 9

parallel processors

Answer 9

allows different parts of a program to be executed simultaneously, or multiple processes

Question 10

heuristic

Answer 10

a problem-solving method that uses shortcuts to produce good-enough solutions given a limited time frame or deadline, using rule of thumbs

Question 11

BRA

Answer 11

branch always, jump instruction that is always executed.

Question 12

BRP

Answer 12

branch if the value in the accumulator is positive

Question 13

sequence

Answer 13

execution of statements or functions one after another

Question 14

selection

Answer 14

where flow of a program is interrupted and control is passed to another point

Question 15

recursion

Answer 15

where a procedure or function calls itself, called a divide and conquer approach

Question 16

global variable

Answer 16

a variable that is accessible from anywhere in the program. useful when a variable needs updating from multiple subprograms.

Question 17

local variable

Answer 17

a variable declared and accessible from inside a subprogram, makes them less likely to be accidentally altered by other modules

Question 18

function

Answer 18

an algorithm that takes an input and produces an output

Question 19

procedures

Answer 19

subprograms that do not return a value

Question 20

by reference (by ref)

Answer 20

passing a value by reference calls on the memory address the variable is stored in, it works directly with the original data and can therefore change it permanently.

Question 21

by value (by val)

Answer 21

used to create a copy of a variable for temporary changes to the variable that will be lost when the function is no longer in use

Question 22

source code

Answer 22

code written in a programming language that can be read and edited by other programmers

Question 23

build

Answer 23

all actions taken to produce a finished working program: writing, compiling, linking, testing, packaging and documentation

Question 24

IDE

Answer 24

integrated development environment, a place to write source code and test it

Question 25

immutable

Answer 25

unchangeable

Question 26

linear search

Answer 26

searching each location one after another until the searched for value is found

Question 27

binary search

Answer 27

dividing the list into two each time until we find the item being searched for (only works on sorted lists)

Question 28

bubble sort

Answer 28

goes linearly through a list, swapping items in the wrong order until no swaps take place in a pass.

Question 29

insertion sort

Answer 29

divides a list in two sorted and unsorted, and goes through the unsorted list, inserting elements from the unsorted list into the sorted where relevant

Question 30

merge sort

Answer 30

Merge sort repeatedly breaks down a list into several sublists until each sublist consists of a single element and merging those sublists in a manner that results into a sorted list.

Question 31

quick sort

Answer 31

It works by selecting a 'pivot' element from the array and partitioning the other elements into two sub-arrays, according to whether they are less than or greater than the pivot. The sub-arrays are then sorted recursively.

Question 32

Big o notation

Answer 32

used to show the time or space needed to execute a function on increasingly sized data

Question 33

complexity

Answer 33

how well an algorithm scales to larger data sets

Question 34

constant complexity o(1)

Answer 34

takes the same time to run regardless of the data set

Question 35

linear complexity o(n)

Answer 35

complexity increases at the same rate as the input size increases

Question 36

polynomial complextiy o(nk) (where k>=0)

Answer 36

complextity increases by a square number, creating a half parabola

Question 37

exponential complexity o(kn) (where k>1)

Answer 37

do not scale well at all

Question 38

logarithmic compexity o(log n)

Answer 38

the rate if complexity increase, decreases as the data set increases. scales extremely well

Question 39

procedural programming

Answer 39

a program where instructions are given in a sequence

Question 40

logic programming

Answer 40

a problem is stated as a set if facts which are used to find a given goal.

Question 41

functional programming

Answer 41

a description of the solution is built up through a collection of functions

Question 42

declarative programming

Answer 42

tell the computer the qualities the solution should have. e.g. SQL

Question 43

opcode

Answer 43

instructions

Question 44

operand

Answer 44

data

Question 45

direct addressing

Answer 45

link directly to a memory location

Question 46

immediate addressing

Answer 46

where the operand is the value we need, not a link to the values memory location

Question 47

inheritance

Answer 47

allows us to create a class with all the methods and attributes of another parent class, as well as building on it to have attributes and methods of its own

Question 48

polymorphism

Answer 48

when methods behave differently according to the context they are used in

Question 49

encapsulation

Answer 49

the pattern of making attributes in a class private but allowing them to be changed and accessed through public methods

Question 50

private

Answer 50

only accessible from within that class

Question 51

applications software

Answer 51

allows a user to perform a task or produce something

Question 52

word processors

Answer 52

used for writing letters, reports and other documents

Question 53

spreadsheet packages

Answer 53

allow users to model complex situations and are often used for financial calculation

Question 54

utility software

Answer 54

relatively small program that has one purpose, usually concerned with system maintenance

Question 55

anti virus programs

Answer 55

detects and removes viruses

Question 56

disk defragmentation

Answer 56

groups all parts of a file together so they can be read faster, instead of the parts of a file being scattered around memory

Question 57

compression programs

Answer 57

reduces the amount of space data takes up in storage

Question 58

file managers

Answer 58

allow files and directories to be moved, copied, deleted and renamed

Question 59

backup utilities

Answer 59

these allow backups to be automatically made of specified data

Question 60

operating system

Answer 60

software that manages the computer: manages hardware, installing and running, security and interface

Question 61

multi tasking operating system

Answer 61

carrying out progressing for more than one thing by switching between tasks giving the illusion theyre working simultaneously

Question 62

multi user operating system

Answer 62

allows more than one person to share a computers resources at the same time

Question 63

distributed operating system

Answer 63

can control and coordinate many computers presenting them to the end user as though they were a single system

Question 64

embedded operating system

Answer 64

computers built to perform one specific job, often more efficient and low powered

Question 65

real time operating system

Answer 65

designed to carry out actions with a guaranteed amount of time even when left running for long periods

Question 66

kernel

Answer 66

helps manage the system resources, including memory management and scheduling

Question 67

memory management

Answer 67

allows programs to be stored in memory safely and effiencently, prevents programs changing each others data, efficient

Question 68

virtual memory

Answer 68

secondary storage that appears as if its in the RAM, when its needed it will be moved back into the RAM, used when the RAM is full

Question 69

scheduling

Answer 69

a program that manages the amount of time different processes have in the CPU

Question 70

round Robin scheduling

Answer 70

each process is given a fixed amount of time

Question 71

First come first served scheduling

Answer 71

the first process to arrive is dealt with firsr

Question 72

shortest job first

Answer 72

performs the shortest job in the queue first

Question 73

shortest remaining time

Answer 73

picks the process that will take the least amount of time to perform

Question 74

multi level feedback queues

Answer 74

uses multiple queues with a different priority level, and moves jobs between these queues depending on the jobs behaviour

Question 75

interrupts

Answer 75

when a device sends a signal to the processor to get attention

Question 76

polling

Answer 76

when the CPU keeps checking each peripheral to see if it needs attention

Question 77

interrupt service routines (ISR)

Answer 77

if an interrupt has a higher priority level than the current one it will move to servicing the new interrupt instead

Question 78

device drivers

Answer 78

tells the operating system how to communicate with a device

Question 79

virtual machines

Answer 79

a program that has the same functionality as a physical computer that runs on a computer

Question 80

BIOS

Answer 80

basic input output system- gets the computer running, checks functionality installed memory and starts the processor

Question 81

open source software

Answer 81

source code is available and can be modified, free

Question 82

closed source software

Answer 82

commercial software that is paid for and the source code is hidden