1.2.2 Applications Generation

Question 1

applications software

Answer 1

• used by the end user to perform a specific task
• needs system software to run
• eg. word processing, spreadsheets, web browser, presentation software

Question 2

systems software

Answer 2

• interacts with hardware
• provides a platform for application software
• manages memory
• provides a ui
• eg. library, utility programs, os, device drivers

Question 3

utility

Answer 3

• program with one purpose
• piece of system software
• used for the maintenance/upkeep of the system

Question 4

defragmentation

Answer 4

• rearranges the contents of the hard drive => accessed faster
• keeps optimal read/write speed for hard drive disk

Question 5

antivirus

Answer 5

finds/removes/detects any threats eg. malware/worms etc.

Question 6

open source

Answer 6

• anyone has permission to amend/recompile/redistribute
• users modify software to suit needs
• free
• anyone can help find security holes, but anyone can exploit

Question 7

closed source

Answer 7

• no source code supplied
• developed by companies with lots of resources => more polished

Question 8

assembler

Answer 8

translates assembly code/low level languages to machine code

Question 9

compiler

Answer 9

• translates the whole program from high level languages into machine code
• hardware specific so source code is hidden

Question 10

interpreter

Answer 10

• translates code from a high level language line by line
• not hardware specific so source code is exposed

Question 11

bytecode

Answer 11

• in java, code is compiled to bytecode => runs on any machine w/ JVM installed
• not hardware specific so code is hidden

Question 12

lexical analysis

Answer 12

• code is converted into a standardised form => easily understandable by machines
• comments/white space removed
• keywords/identifiers replaced w/ tokens
• lexer creates symbol table

Question 13

syntax analysis

Answer 13

• code is checked/syntax checked to see if it is valid based on the rules of the language
• using an abstract syntax tree => errors generated if rules are broken

Question 14

code generation

Answer 14

abstract syntax tree converted to machine/object code

Question 15

optimisation

Answer 15

• redundant parts of code are removed to reduce execution time/improve efficiency
• time-consuming

Question 16

library

Answer 16

a set of prewritten/precompiled functions that can be imported & reused in code

Question 17

linker

Answer 17

combines compiled code with code from library into a single executable file

Question 18

loader

Answer 18

• part of the os
• copies program/any linked subroutines => main memory