1.5 Systems software

Question 1

What is an operating system

Answer 1

a group of programs that manages the computer’s resources

Question 2

what functions does the operating system provide

Answer 2

• providing a user interface
• memory management
• peripheral management
• user management
• file management

Question 3

what are the types of user interface

Answer 3

• Graphical user interface [WIMP (windows, icons, menus, pointers)]
• Command-line interface
• Menu interface
• natural language interface

Question 4

what does a user interface do

Answer 4

provide the way in which you interact with the computer as a human being

Question 5

describe a graphical user interface

Answer 5

• visual, interactive
• windows, icons, menus, pointers

Question 6

describe a command-line user interface

Answer 6

• text based
• more commands to learn so for advanced users
• efficient and less resource heavy

Question 7

describe a natural language user interface

Answer 7

• responds to questions in a spoken language
• not always reliable but getting better all the time

Question 8

describe a menu user interface

Answer 8

• successive menus presented to the user
• single options chosen at each stage
• often interacted with through buttons on a keypad
  (eg. cash removal point)

Question 9

describe how the operating system performs memory management

Answer 9

• over time the memory becomes fragmented as programs are loaded and closed because they use different amounts of memory
• when new programs are loaded into memory, the packets are separate and have to be put wherever there is space
• the operating system shuffles the packets together to collect free space for the incoming programs

Question 10

why is fragmentation bad

Answer 10

all the packets are spread out so it is inefficient for the moving read/write head to have to collect each one individually. this appears to the user as the computer running slowly

Question 11

on what storage device is a defragmentation system needed

Answer 11

• magnetic hard disks

Question 12

on what storage device is a defragmentation system not needed

Answer 12

solid state drive as it has no moving parts. defragmentation would actually decrease its life span

Question 13

what is multi tasking

Answer 13

when a computer switches rapidly between several tasks

Question 14

how is multi tasking performed on a computer

Answer 14

The processor allocates a small amount of time to each process and cycles between them. this is so it appears to the user as if they are all working simultaneously

Question 15

what is a peripheral of a computer

Answer 15

any computer hardware components that are not the CPU. Peripherals include input, output and storage devices.

Question 16

how does the operating system manage peripherals

Answer 16

it uses a device driver which translates the operating system instructions to print the document into a series of instructions which a specific piece of hardware will understand. this means you can print the same document and it will look the same no matter what type of printing technology is used.

Question 17

what is buffering

Answer 17

used to compensate for the difference in speeds between the rate that data is received for printing or streaming and the rate at which it can be printed or streamed

Question 18

what is a data buffer

Answer 18

• an area of RAM controlled by the peripheral management system.
• when you give the command to print a document (for example) the data is copied to the print buffer, the print management system retrieves the data from the buffer and sends it to the printer
• if the buffer is not big enough to hold all the data, the buffer will be refilled during printing as space becomes available

Question 19

what does the user management system do

Answer 19

enables a network administrator to allocate accounts and set different access rights for different users
- the system can also
=identify all users on a network
=manually log out users
=monitor when and how long each user is logged in

Question 20

functions of the user management system

Answer 20

control
- allocation of an account
- access rights
- security

Question 21

why does a computer need a file management system

Answer 21

to support the creation, copying, moving, deletion and renaming of files and folders

Question 22

what things does a file management system do

Answer 22

• allows the user to rename, move, delete and copy files
• help set permissions and access rights
• allow user to sort files into folders and directories

Question 23

purpose and functionality of utility software

Answer 23

…

Question 24

What types of utility system software are there

Answer 24

• encryption software
• defragmentation
• data compression

Question 25

purpose of encryption software

Answer 25

helps to keep sensitive data safe from cyber-criminals or unauthorised access

Question 26

how does encryption software work

Answer 26

uses an algorithm to convert plain text into cipher text. the text can only be decrypted and made readable again with a key

Question 27

purpose of defragmentation software

Answer 27

collects free space which reduces the movement of the read/write head so that the computer appears to run faster

Question 28

how does defragmentation software work

Answer 28

juggles the contents of memory sectors to keep files together as much as possible

Question 29

purpose of data compression software

Answer 29

makes the file size smaller so that:
- less storage space is needed
- it is faster to download and upload files
- better performance is achieved when streaming

Question 30

understand that computers often come with utility software and how this performs housekeeping tasks

Answer 30

.