[Unit 1.2.2] Applications Generation

Question 1

define “applications software”

Answer 1

allows user to perform a task or produce something

Question 2

what are the 8 different applications

Answer 2

word processors
spreadsheet software
presentation software
database software
desktop publishing software
image editors
web browsers
games

Question 3

what are the advantages of applications becoming more cloud based

Answer 3

dont worry about installation
dont worry about updating software
access app anywhere
can collaborate on document with multiple users.

Question 4

define “utility”

Answer 4

program has one specific purpose - usually maintenance. (built in or stand alone)

Question 5

what are the 9 different types of utility programs

Answer 5

defragmentation
anti-malware
disk checkers
disk formatters
partitioning software
compression software
file explorers
backup utilities
encryption software

Question 6

what is defragmentation

Answer 6

file split up in multiple sections, slows computer
defragmentation software groups each file contiguously. and groups free space together at the end

Question 7

what is anti-malware software

Answer 7

detects and blocks threats

Question 8

what are disk checkers

Answer 8

check for corrupted files

Question 9

what are disk formatters

Answer 9

prepare device to store files, erasing previous content

Question 10

what is partitioning software

Answer 10

dividing up space so OS sees as separate devices

Question 11

what is compression software

Answer 11

reduce data in files by recognising patterns that are repeated.
save space, faster to transmit

Question 12

what are file explorers

Answer 12

manage data storage
allow files to move,copy,delete, rename

Question 13

what are backup utilities

Answer 13

automatic backups of specified data
copied to a different location in case original is corrupted
ensures important data is safe

Question 14

what is encryption software

Answer 14

data scrambled into cipher text
vital for transmitting personal data over network.

Question 15

define “closed source software”/”proprietary software”

Answer 15

executable machine code file distributed.
by commercially sold software

Question 16

what are the advantages of closed source software

Answer 16

more polished
customer support
reliability
warranty/guarantee

Question 17

what does “more polished” mean when talking about open/closed source software

Answer 17

easier to install
easier to use
more attractive UI

Question 18

what are the disadvantages of closed source software

Answer 18

expensive
users cant change code
bugs only fixed by company
older versions not maintained

Question 19

define “open source software” (OSS)

Answer 19

publicly available source code that can be modified and distributed

Question 20

what are the advantages of OSS

Answer 20

free
user can add features
user can fix bugs
software rapidly developed
older software supported

Question 21

what are the disadvantages of OSS

Answer 21

doesn’t come with warranty/guarantee
doesn’t have customer support
may not get regular updates
less polished

Question 22

define “low level language”

Answer 22

specific to instruction set of processor.
they are not portable
low level of abstraction

Question 23

define “portable” in terms of translators

Answer 23

can be used on different types of CPUs

Question 24

define “high level language”

Answer 24

human readable, high level of abstraction
code is portable
one line is multiple lines of machine code

Question 25

define "translator"

Answer 25

software converts source code into machine code

Question 26

what are the three types of translator

Answer 26

assembler compiler interpreter

Question 27

what are the two parts to machine code

Answer 27

opcode operand

Question 28

define "opcode"

Answer 28

tells CPU what operation to do (add store etc)

Question 29

define "operand"

Answer 29

tells CPU what data to use in operation

Question 30

define "assembly code"

Answer 30

uses mnemonics to represent opcodes 1:1 line ratio not portable fast and efficient as high control over CPU and hardware

Question 31

what is assembly code used for

Answer 31

embedded systems device drivers

Question 32

define "assembler"

Answer 32

program converts assembly to machine code

Question 33

define "compiler"

Answer 33

whole program converted from high level language to machine code in one go creating executable machine code file

Question 34

what are the advantages of a compiler

Answer 34

runs faster (only translates once) executable code cant be read (closed source software)

Question 35

what are the disadvantages of a compiler

Answer 35

must wait for entire program to translate if change is made, recompile whole program executable code is specific to instruction set

Question 36

define "interpreter"

Answer 36

translates source code one line at a time

Question 37

what are the advantages of an interpreter

Answer 37

errors shown line by line errors reported as encountered (dont wait for whole program to translate) run on any platform (that has interpreter)

Question 38

what are the disadvantages of an interpreter

Answer 38

must have interpreter installed interpreter takes up memory translating line by line is slower than running compiled machine code source code must be available to user

Question 39

what are the four stages of compilation

Answer 39

lexical analysis syntax analysis code generation code optimisation

Question 40

what is lexical analysis stage of compilation

Answer 40

source code read character by character and broken into tokens. identifies basic syntax errors (misspelled key words)

Question 41

what is removed during lexical analysis

Answer 41

comments and white space

Question 42

what is syntax analysis of compilation

Answer 42

source code checked by parser to ensure it follows rules of programming language. if an error is found it is added to the compiler report

Question 43

what does the parser produce during syntax analysis

Answer 43

Abstract Syntax Tree (AST)

Question 44

what is the purpose of producing a AST during syntax analysis

Answer 44

removes unnecessary syntax like parenthesis simplifies code optimisation helps understand hierarchy of operations

Question 45

what is the code generation stage of compilation

Answer 45

compiler converts source code into object code

Question 46

what is the code optimisation stage of compilation

Answer 46

compiler tweaks source code to improve performance

Question 47

when does code optimisation happen during compilation

Answer 47

throughout the entire process

Question 48

what does code optimisation, optimise for during compilation

Answer 48

optimises for speed OR memory efficiency.

Question 49

what is a library

Answer 49

collection of pre-written code developers reuse

Question 50

what are the advantages of libraries

Answer 50

no need to rewrite code already tested and debugged app remains small some functionality requires specific expertise

Question 51

what are the disadvantages of libraries

Answer 51

library must be well written and robust specialist libraries can be expensive if library is missing program will crash

Question 52

what is a linker

Answer 52

software that combines libraries with object code to create a single executable file

Question 53

what is an API

Answer 53

application programming interface allows different computer programs to interact with each other (how you use libraries)

Question 54

how does a linker work

Answer 54

when compiled, object file contains references to libraries. linker resolves these references

Question 55

what is a static linked library

Answer 55

library code put directly into program end user doesn't have to have library installed increases the file size

Question 56

what is a dynamic linked library

Answer 56

libraries not added to code. libraries stored by OS and loaded when program runs. makes program smaller user must have library installed

Question 57

what is the loader

Answer 57

part of the OS that's responsible for loading the executable file into memory from secondary storage.