1.2.2 Applications Generation

Question 1

1.2.2 A)
What are the natures of software

Answer 1

Software can either application software or system software.

Question 2

1.2.2 A)
What is system software

Answer 2

system software is low level software that is responsible for running the computer system smoothly interacting with hardware providing a platform for application software to run.
Example: utility programs, OS , device drivers

Question 3

1.2.2 A)
What is Application software

Answer 3

designed to be used by the end user to preform one specific task. app software needs system software
Example : word , spreadsheet

Question 4

1.2.2 B)
Define utility

Answer 4

piece of system software that ensures consistent and high performance from the OS .

Question 5

1.2.2 B)
What are examples of utility

Answer 5

Compression
Disk defragmentation
Anti-virus
Auto-updating
Backup

Question 6

1.2.2 B)
What are examples of utility
What is compression

Answer 6

Enable files to be compressed and decompressed used to send large files

Question 7

1.2.2 B)
What are examples of utility
What is disk defragmenation

Answer 7

as disk becomes full, slow r/w cos files are fragmented. This rearranges content so faster to r/w . ^ performance

Question 8

1.2.2 B)
What are examples of utility
What is antivirus

Answer 8

Detects potential threats to the computer

Question 9

1.2.2 B)
What are examples of utility
What is auto updating

Answer 9

ensure OS is up to date. tracks bugs / security flaws makes device less vulnerable.

Question 10

1.2.2 B)
What are examples of utility
What is backup

Answer 10

automatically creates routine copies of specific files selected by user meaning recovery.

Question 11

1.2.2 C)
What is source code and object code
whats the difference

Answer 11

soruce code is object code before its translated - high level
object code is source code after its translated - low level

Question 12

1.2.2 C)
Define open source

Answer 12

can be used by anyone w/o license

Question 13

1.2.2 C)
Define closed source

Answer 13

requires license can be access source code company owns rights.

Question 14

1.2.2 C)
Adv / DAdv of open source

Answer 14

Adv ) modify / improve by anyone , support from community , modified and sold on.
DAdv ) online support may be wrong , lower security

Question 15

1.2.2 C)
Adv / DAdv of closed source

Answer 15

Adv) well tested updated , expert support, ^ level security
DAdv) license is restricting, user cannot modify and / or improve

Question 16

1.2.2 C)
How to know weather open or closed

Answer 16

Suitability of the software to the task it will be used for,
cost: maintenance/ staff/ licence, functionality - ease of use

Question 17

1.2.2 D)
What is a translator

Answer 17

program that converts high level source code into low level object code

Question 18

1.2.2 D)
properties of a compiler

Answer 18

Translates all at once
Shows errors at the end
Needs to be recompiled when changes made
initially longer then interpreter and assembler
complier code is specific to a processor type
used to produce intermediate code

Question 19

1.2.2 D)
properties of an interpreter

Answer 19

translates and executes one line at a time stops at error
may be faster but slower at running compiled code
used for testing sections of code don’t need to run all
more portable

Question 20

1.2.2 D)
properties of an assembler

Answer 20

low level language next up from machine code
platform specific
instructions used is dependant on Instruction set
assembler translates assembly code into machine code
1 line of AC is almost 1 line of MC so almost 1 to 1

Question 21

1.2.2 E)
What are the stages of compilation

Answer 21

1) Lexical analysis
2) syntax analysis
3)code generation
4)optimisation

Question 22

1.2.2 E)
What are the stages of compilation
What happens at lexical analysis

Answer 22

white spaces and comments removed
remaining code analysed for keywords
also variables and contestants
these are replaced with token
information about these stores in symbol table

Question 23

1.2.2 E)
What are the stages of compilation
What happens at syntax analysis

Answer 23

tokens are analysed against grammar and rules of lang
any breaking rules are flagged
abstract syntax tree produced ( code in a tree)
more details abt identifiers added to symbol tree (data type / scope / address)
semantic analysis logical errors detected
passes code to code generation

Question 24

1.2.2 E)
What are the stages of compilation
What happens at code generation

Answer 24

Abstract tree produced in syntax analysis is used to produce machine code

Question 25

1.2.2 E)
What are the stages of compilation
What happens at optimisation

Answer 25

aim to make code faster to execute. reduce time taken for compiler redundant code is removed

Question 26

1.2.2 F)
What’s a linker

Answer 26

responsible for linking external modules and libraries within code

Question 27

1.2.2 F)
What are the two type of linkers

Answer 27

static and dynamic

Question 28

1.2.2 F)
What is a static linker
whats the -ve of working this way

Answer 28

(subroutine) Modules / libraries added directly into main file , ^ file size , external update wont effect program

Question 29

1.2.2 F)
What is a dynamic linker
whats +ve of working in this way

Answer 29

Address of modules (subroutine) / libraries included in file . loaders retrieve program from specific address. file remains same size

Question 30

1.2.2 F)
What is a loader

Answer 30

when files execute loaders retries the library/ subroutine (modules) from memory

Question 31

1.2.2 F)
What is a library

Answer 31

Pre-complied programs. ready to use, save time reusable using linkers