1.5 - Systems software

What is software?

Computer programs that consist of instructions that tell the computer what to do

What are the two types of software?

• Systems software

• Application software (end-user designed to perform specific tasks)

What is systems software and give examples

Systems software are the foundational computer programs of a computer system; they manage and control the hardware, provide a platform for applications to run and users to interact with and ensure the computer system operates securely and efficiently.

• Operating system (OS)

• Utility software

• Device drivers

What is the purpose of the operating system?

The operating system is a type of systems software.

It is a group of programs that run all the time to help manage the resources of the computer system and provide the interface between the user and the computer’s hardware.

eg. ChromeOS is the operating system of a chromebook

Give the functions of the operating system

• Memory management and multitasking

• Provides a user interface

• File management

• User management

• Peripheral management and drivers

Explain how the operating system manages memory and allows multitasking

The operating system manages how memory is used.

• It allocates memory to programs and data in RAM when they are currently in use

• De-allocates memory from programs and data when they are no longer in use to free up that memory space for other programs

• Transfer of data between memory (a program is copied from secondary storage to RAM; data may be moved to different parts of RAM as a program is running; moved between RAM and registers; moved from RAM back to secondary storage for long-term storage)

• Keeps programs separate so they don’t overwrite each other

• Manages virtual memory when RAM is full

It ensures that the computer runs smoothly and that programs have enough memory space to work

The operating system allows multitasking, which is the ability to switch rapidly between multiple programs so that it appears as if multiple tasks are being processed simultaneously.

Why is memory management important?

The CPU can only process data and programs stored in RAM, so data and programs must be transferred from secondary storage into RAM to be processed.

What does the user interface allow?, and give examples of features of different user interfaces

The operating system allows the user to interact with the computer system.

GUI (graphical user interface):

(WIMP)

• Windows - separate areas on the screen to visibly show different programs or applications

• Icons - small images representing files, folders or applications

• Menus - shows lists of options or actions

• Pointers - used to select and interact with items

Command line interface:

• Lets the user type in text commands to control the computer

• Requires knowledge of command syntax

• Provides a simple and direct means of control

Other types:

• touch-sensitive interface

• voice-sensitive interface

• menu-driven interface (eg. ATMs)

What is file management? What are the key functions?

It is a function of the operating system that creates and maintains a logical management system to organise files and folders.

• creates and deletes files

• organises and allocates files into folders

• moves files

• names and renames files

• opens and closes files

• copies files

• saves files

• searches for files

• sorts files

• controls access to files (access rights)

What is user management? What are the key functions?

It is a function of the operating system that controls what accounts can use the computer system and what they can do.

• allocation of an account

• setting access rights

• create account

• delete account

• manage security (eg. allowing passwords to be set, monitering user activity)

What is meant by a peripheral?

A device that is not a part of the CPU (including input, output and storage devices (eg. hard disk).

What is peripheral management and device drivers?

Peripheral management is the operating system’s job of controlling and communicating with external devices (peripherals) connected to the computer; it manages the transfer of data between devices and the processor.

• Sends data to peripherals

• Receives data from peripherals

A device driver is a small program that provides an interface for the OS to interact and communicate with a specific peripheral.

Device drivers are hardware (peripheral) dependent and OS specific.

• The device driver translates OS commands into instructions the device can understand

What is utility software and what do they do?

Utility software is a type of systems software. They are non-essential, dedicated programs that are used for maintenance, organisation (housekeeping tasks) and security of a computer system which allow the computer system to run more efficiently and safely.

Utilities are required to run additional tasks not performed by the operating system

Why is utility software needed on a computer system?

• To perform housekeeping tasks (maintenance, organisation)

• To help the computer system to run efficiently

It is needed to perform specific tasks that may not be carried out by the operating system

Give examples of utility system software

• Encryption software

• De-fragmentation

• Data compression

Give the purpose of encryption software and why it is required

Encryption software is a type of utility software that secures sensitive data by converting it into cyphertext using an algorithm and a key so that people without the key cannot interpret it.

It is required to:

• prevent unauthorised access to data

• maintain data security (data protection act 2018)

• protect against cyber criminals

Give the purpose of defragmentation software and why it is required

(Required for HDDs)

Defragmentation software is a type of utility software that reorganises files on a hard drive by collecting empty spaces together so that file fragments can be moved and stored together.

• Means fewer disc accesses are needed, requiring less physical movement so file fragments can be read consecutively. This makes them quicker to access and more efficient

• Frees up space and reduces wasted storage caused by defragmentation

• Reduces wear of the hard drive

Give the purpose of data compression software and why it is required

Data compression software is a type of utility software that reduces the size of files or data so that they take up less storage space, or can be transmitted more quickly.

• Efficient use of storage

• Faster file transfer

• Cost saving