Chapter 4 - Software Flashcards
Types of software (hierarchy of software and hardware)
Application software
System software
Hardware
Examples of Application software (8)
Programs that allow users to do specific tasks
Data base - used to organise, analyse and manipulate data
Spreadsheet - organise and manipulate numericalk data
Word processor - used to manipulate text data
Control+measuring software - allows microprocessor to interface with sensors to measure physical quantities etc
Photo editing software - manipulate stored digital photographs
Video editing software - manipulate videos to produce new videos
Graphics manipulation software - allows bitmap and vector images (lines,curves and text) to be changed
Apps - applications, downloaded from appstore, banking, gaming etc
General features of application software (4)
Used to perform various applications on a computer
Allows a user to perform specific tasks using a computers resources
May be a single program (NotePad) or a suite of programs (microsoft office)
User can execute the software as they require
Utility programs offered by most computer systems (7)
Virus checkers
Defragmentation software
Disk contents analysis and repair
File compression and management
Back up software
Security
Screesavers
General features of system software (5)
Set of programs to manage the operation of computer hardware
Requires a platform on which other software cun run
Required to allow software to run without problems
Provides Human Command Interface (HCI)
Controls allocation and usage of hardware resources
WIMP
Windows Icons Mice and Pointing device
Set of software features and hardware devices designed to simplify computing operations for the user.
System software (5)
Programs that allow the hardware to run properly and allow the user to communicate with the computer
Compilers - translates programs written in HLL into machine code
Utilities - software designed to carry out specific tasks on the computer
Device drivers - software that enables 1+ hardware devices to comunicate with the OS
Operating Systems -
Linkers-takes 1+ object files produced by compiler and combines them into a single program to be run on the computer.
Common features of anti virus software (6)
Heuristic checking- checking software for behaviour that could indicate a virus
Must be kept up to date
Quarintine files/programs, auto deleting them or allowing the user to delete them
Full system scans done once a week to check for dormant viruses
Compares a possible virus against known data
Check software/files before they are run or loaded onto a computer
Quarantine
To isolate a file identified by anti virus software as having a virus
False positive
One of the drawbacks of anti-virus software, the software believes the file is infected but it isnt
Defragmentation software
Software that reorginises sectors on HDD by rearanging blocks of data so that they are contiguous, improving data access by reducing HDD read-write head movements
Back up utility
Creates a backing up schedule for files and only back up once changes have been made
Creates 3 versions of the file:
-Current - internal HDD/SDD
-Local-portable SDD
-Remote-Cloud storage
What microsoft windows offers using back up utilities (4)
Restore data, files or computer from the backup
Create a restore point (time machine-can restore computer to a previous state)
Options of where to save backup files
File history - you have to switch it on, takes snapshots and stores them allowing the user to choose a file version from the library created
What Mac OS offers using back up utilities
Time machine
Erases contents of selected drive and replaces it with contents from back up.
Need an external HDD or SDD connected via USB port to ensure it is effectively stored
Automatically backs up every hour, day and week
Security software(5)
Over arching utility that
protects network interfaces (use of firewalls)
overseas updating of software (does it come from a legit source?)
links into other utility software (virus checkers etc)
encrypts and decrypts to ensure intercepted data is useless without a key
manages control and user accounts using IP addresses and passwords
Types of system software (5)
Utility programs
Operating systems
Linkers
Compilers
Device drivers
Device drivers
Software that communicates with operating system and translates data into a format that can be understood by hardware peripheral devices to stop them from saying “device not recognised”.
Contain descriptors, collections of data about a device plugged into the USB port, can be Vendor ID OR Product ID or serial number. If the device plugged in has no serial number associated with it the OS will treat it as a new device
Screensavers
Programs that provide still or moving images on the computer monitor after periods of inactivity. Originally developed to protect the old Cathode Ray Tubes from phosphorus burn and is not neccessary on new OLED and LCD screens but serves as an extra layer of security as it logs you out after a period of inactivity.
Used during virus scans and distributed computing applications (allow apps to use computers resources when idle)
Operating system functions (9)
Multitasking
HCI - Human Computer Interface
Platform for running application software
Management of user accounts
Managing files
Managing peripherals and drivers
Memory management
Interrupt handling routines
Providing system Security
Operating systems
Enable computer systems to function correctly and allows users to communicate with computer systems by providing an enviroment in which applications can run as well as a useable interface between computers and humans. Disguises complexity of computer software eg. microsoft windows, Apple Mac OS, google android.
where do computers and phones store the operating system
Computers store it on HDD or SDD since they are large programs
Phones store it on SSD since they are to small to have an HDD
What happens to backups when the SSD or HDD is almost full
The oldest backups are deleted and replaced
CLI
Command line interface
Interface that allows communication with the computer by typing in commands using a keyboard
GUI
Graphical User interface
Interface that allows users to interact with computers usingicons to represent apps and tasks that a user can click on using a mouse or touch screen (WIMP + post WIMP )
Post WIMP
Modern touch screen that uses pinching, rotating and tapping to select icons.
Who would use CLI
Someone who needs direct communication with a computer to develop new software or look for and fix errors. Programmer, analyst, technician.
Who would use GUI
End user with limited knowledge on how computers work. Use computers to run software, play games and edit photos.
Advantages of CLI (4)
Allows for direct communication with computer
Not limited to predetermined options
Possible to alter computer figuration settings
Uses a small amount of computer memory
Disadvantages of CLI (3)
User has to memorise commands in order to carry out basic functions
Takes time to type in commands and there can be mistakes
Commands must be typed with specific spelling and format
Advantages of GUI
Much more user friendly
Simpler as all you have to do to launch an application is click on an icon
Dont have to memorise commands
Disadvantages of GUI (3)
Limited to icons on the screen
Uses more memory than CLI
Requires an operating system to function which uses up even more memory
Memory management
Software that manages the primary storage (RAM) and the moving of data from RAM to HDD/SSD
Keeps track of all memory locations
Carries out memory protection to ensure 2 competing applications dont store data in the same memory loaction as it could lead to lost data, incorrect results produced by the applications and the computer crashing
EEPROM
Electronically Erasable Programmable ROM
Boot up/bootstrap loader
Small program used to load other programs to correctly start up a computer system
Security management
Part of operating system that ensures integrity, confidentiality and accessability of data.
Features of security management (7)
Prevents illegal intrusion into the computer
Maintains users access rights
Sets up user accounts using passwords and user IDs on multi user devices to prevent access to “ptivate areas”
Communicates with the firewall to examine the traffic flow
Carries out OS updates when available
Ensures security software is up-to-date
Offers the ability to restore lost or corrupted data and to restore the system
Buffer
Memory area to temporarily store data
Hardware and peripheral management
Part of the operating system that controls all input and output devices and is made up of sub systems such as printing management