01 - Section 1 - Types of software

Question 1

What does the operating system do in basic terms?

Answer 1

Operating systems manage hardware and run software

Question 2

What are the main functions of an operating system?

Answer 2

• communicate with internal and external hardware via the device drivers
• provides a user interface
• provides a platform for different applications to run
• allows the computer to ‘multi-task’ by controlling memory resources and the CPU
• deal with file management and disc management

Question 3

What do device drivers do?

Answer 3

Device drivers allow the OS and Hardware interact (communicate) with each other
-internal hardware and peripherals

Question 4

What does every piece of hardware connected to a computer system need?

Answer 4

a device driver

-they will effectively act as a ‘translator’ for the signals between the OS and hardware

Question 5

When a computer is booted up what does the OS do in regards to the device driver?

Answer 5

The OS will choose the correct device driver for the hardware it detects

Question 6

Why are new device drivers released sometimes?

Answer 6

Device manufacturers may release updates to device drivers in order to fix bugs or improve the performance
-updates may be installed automatically by the OS or manually by the user

Question 7

What does a user interface allow?

Answer 7

A User Interface allows the user to interact with a computer system

Question 8

What does GUI stand for?

Answer 8

Graphical User Interface

Question 9

What are GUIs?

Answer 9

They are a type of user interface designed to be easy for everyday users by making them visual, interactive and intuitive

Question 10

What have GUIs been optimised for overtime?

Answer 10

GUIs have been optimised for different input methods

• in the past used to be WIMP-based (using windows, icons, menus and pointers)
• Android and iOS were created for touchscreen devices (finger gestures instead of mouse movement)

Question 11

What is a command-line interface?

Answer 11

A command-line interface is text based
The user enters specific commands to complete tasks
Command line interfaces are less resource-heavy than GUIs

Question 12

Who would use command-line interfaces?

Answer 12

Advanced users can find command-line interfaces to be far more efficient and powerful than GUIs
-used to automate processes using scripts

Question 13

What provides a platform for running applications?

Answer 13

Operating systems

Question 14

What are operating systems which can run multiple applications called?

Answer 14

multi-tasking OSs

Question 15

How does the OS help the CPU carry out multi-tasking?

Answer 15

By efficiently managing memory and CPU processing time

Question 16

How does then OS manage memory for the CPU?

Answer 16

• when an application is opened, the OS moves the necessary parts to memory, also parts when they are required
• OS decides if applications or features have been recently used, if not they may be removed from memory
• to run multiple apps, the OS makes sure apps don’t overwrite or interfere with each other

Question 17

What does a memory manager do?

Answer 17

It allocates certain memory addresses, to make sure their processes are placed into separate locations

Question 18

How does the OS manage CPU processing time?

Answer 18

• only one application is processed by the CPU at a time, the others wait
• OS divides the time between open application, by prioritising certain processes(most efficient order)
• when required, the OS organises the movement to and from virtual memory

Question 19

What do computers store data as?

Answer 19

files

-images, music, videos etc. are all just collections of data

Question 20

What do file extensions do?

Answer 20

File extensions (e.g. .jpeg .mp3) tell the computer which software should be used to open this file

Question 21

What does the OS do in terms of file management?

Answer 21

• OS is responsible for file management
• file management involves, organising data into a usable hierarchical structure
• OS also seals with the movement, editing and deletion of data

Question 22

How does the OS manage the hard disk?

Answer 22

• it splits the physical disc into storage sectors, decides which to write data to and keeps track of free space on the disk
• ideally the data for a single file would be placed in the same place but this doesn’t always happen

Question 23

What software does the OS use to organise and maintain the hard disk with?

Answer 23

utility software
(for example defragmentation software)

Question 24

What are the two options for how OSs deal with user accounts?

Answer 24

single-user

multi-user

Question 25

What are example of single-user OSs?

Answer 25

Windows 10 | OS X

Question 26

What does a single-user OS mean?

Answer 26

It allows one user to use the computer at once

Question 27

What is an example of a multi-user OS?

Answer 27

UNIX server

Question 28

What does a multi-user OS mean?

Answer 28

It allows several users to use the computer at the same time -they use mainframes(huge supercomputers) and give many users simultaineous access at the same time (for example ATMs allow thousands of people access to the banks mainframe at the same time)

Question 29

How does the OS manage user account control?

Answer 29

User accounts allow different users to be granted access to specific data or resources on a computer system

Question 30

What anti-theft measures can OSs have to prevent other users accessing locked devices or accounts to steal information?

Answer 30

- user accounts may be password or pin protected | - some devices also require a user to draw a specific pattern on the screen or have a fingerprint or retina scanner

Question 31

What does defragmentation software do?

Answer 31

It reorganises data on the hard drive to put fragmented files back together. It also moves files to collect all the free space together (to prevent further fragmentation)

Question 32

Why does the hard disk's data become fragmented?

Answer 32

- As files are moved, deleted, and change size, lots of small gaps begin to appear on the disk - when writing files to the disk the OS then splits the files into smaller blocks to fill the gaps

Question 33

What is the problem with disk defragmentation?

Answer 33

-it makes reading and writing files slower as the read/write head has to move back and forth across the disk

Question 34

Is disk fragmentation an issue for SSDs?

Answer 34

As SSDs use flash storage with no moving parts, fragmentation doesn't cause any issues (it can access data quickly however it's arranged) -SSDs actually have a limited read/write times, defragmenting them can actually shorten their life span

Question 35

What is a backup?

Answer 35

A backup is a copy of a computer system's files and settings stored externally -this means data can be recovered if its lost

Question 36

Why can data be lost?

Answer 36

- fire - theft - flood - malware - hardware failure

Question 37

What is a backup utility?

Answer 37

A backup utility is software with facilities such as scheduling of regular backups, creating rescue disks, disk images, and options for full or incremental backup

Question 38

What is a full backup?

Answer 38

It's where a copy is taken of every file on the system. - use a lot of storage space - can take a long time to create - is faster to restore from

Question 39

What is an incremental backup?

Answer 39

Incremental backups are where only the files created or edited since the last backup are copied. - use less storage - quicker to create - a full system restore is slow, the last full back up must be restored, followed by every incremental backup since then

Question 40

What are the four types of backup utilities you need to know?

Answer 40

- full backup - incremental backup - compression software - encryption software

Question 41

What is compression software?

Answer 41

Compression software reduces the size of files so they take up less disk space.

Question 42

When is compression software mainly used?

Answer 42

On the internet to make files quicker to download (standard file formats are .zip .rar)

Question 43

What needs to happen to compressed files before they can be used?

Answer 43

Compressed files need to be extracted before they can be used.

Question 44

What is encryption software?

Answer 44

Encryption software scrambles data to stop third-parties from accessing it. Encrypted data can be decrypted using a special 'key'

Question 45

What is open source software?

Answer 45

Open source software is software where the source code is made freely available. -users may legally modify the source code to create their own spin-off software, which can be shared under the same licence and terms as the original software

Question 46

What are examples of open source software?

Answer 46

``` Apache HTTP server (runs web servers) GIMP (image editing) Firefox (web browser) VLC media player Linux OS (open source operating system) ```

Question 47

What are the advantages of open source software?

Answer 47

- it's (usually) free - made for greater good, not profit (encourages collaboration) - software can be adapted by users to fit their needs - popular software is very reliable and secure (any problems are quickly solved by the community)

Question 48

What are the disadvantages of open source software?

Answer 48

- small projects may not get regular updates (so it could be buggy, have unpatched security holes) - may be limited user documentation - no warranties if something goes wrong - no customer support

Question 49

What is proprietary software?

Answer 49

Proprietary softare is software where only the complied code is released. The source code is usually a close-guarded secret.

Question 50

What do proprietary software licences do?

Answer 50

They restrict the modification, copying and redistribution of the software. It's usually paid for.

Question 51

What are examples of proprietary software?

Answer 51

Microsoft (Office, Windows, Outlook...) | Adobe (Photoshop, Illustrator...)

Question 52

What are the advantages of proprietary software?

Answer 52

- comes with warranties, documentation and customer service - should be well-tested and reliable as the companies reputation depends on this (fixes and updates will come regularly) - usually cheaper for companies then developing their own custom-built software

Question 53

What are the disadvantages of proprietary software?

Answer 53

- can be expensive - software may not exactly fit a user's need - software companies may not maintain older software after warranties expire (to get people to buy their latest product)