Chapter 4 - Software

Application software System software Hardware

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

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

Virus checkers Defragmentation software Disk contents analysis and repair File compression and management Back up software Security Screesavers

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

Windows Icons Mice and Pointing device Set of software features and hardware devices designed to simplify computing operations for the user.

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.

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

To isolate a file identified by anti virus software as having a virus

One of the drawbacks of anti-virus software, the software believes the file is infected but it isnt

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

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

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

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

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

Utility programs Operating systems Linkers Compilers 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

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)

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

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.

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

The oldest backups are deleted and replaced

Command line interface Interface that allows communication with the computer by typing in commands using a keyboard

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 )