INFO 11.7 Selection and use of

appropriate software

Specification

Throughout the lesson you are to tweet on the content covered including:

◦ Key concepts◦ Keywords◦ Questions◦ Opinions◦ Thoughts

Use the hastag #dbs12

twitter

1. What is Software and why is it needed?

2. What are the two main types of software?

3. What are the sub categories of each type of software?

4. What is the purpose of Utilities?

5. Name a least 5 utilities

6. Thoroughly explain the purpose of ‘Device Drivers’

7. Why might a Device Driver fail to function?

8. What is a compiler and how does it work?

9. What is an Interpreter and how does it work?

10. What is an operating system and what is it’s purpose and function?

11. Name 3 operating systems

12. Explain the difference between single and multi tasking operating systems and give examples

13. Explain the purpose of Applications software

14. What are the 3 main categories of software applications?

15. Name 6 common ‘general’ applications

16. State two appropriate uses for each applications software

17. State three features found in each applications software

18. Give examples of 2 specialist applications

19. What is meant by Bespoke?

20. What are 2 advantages of investing in bespoke software?

21. What are 2 disadvantages of investing in bespoke software?

22. State 2 advantages of purchasing off the shelf applications

23. State 2 disadvantages of purchasing off the shelf applications

24. Explain what integrated software packages are

25. What are the benefits and drawbacks of open source software?

26. Explain what is meant by Proprietary Software

27. Why do software manufactures upgrade their software?

28. What must a company consider before upgrading their software?

Learning objectives with a TWIST

Hardware refers to the physical components that make up the computer

Software?

Software refers to the computer programs that make the hardware do something useful

Software can divided into main two categories

Software Types

SystemsSoftware

ApplicationsSoftware

Systems software describes the programs which help the user control and make best use of the hardware

Applications software describes programs that have been written to perform a specific task

Two categories of systems software

Systems Software

Operating Systems Other Systems Software

Systems Software

Utilities Drivers

Compilers &Interpreters

The purpose of utilities are to analyze, configure and maintain the computer

Some common utilities

◦ Anti-Virus◦ Compression◦ Backup/Restore◦ Registry Cleanup◦ Scan disk/disk repair◦ Hardware diagnostics◦ Encryption/decryption

Sometimes included with the Operating System Sometimes bundled/sold together in a separate

package Utility Programs only do one or perhaps two tasks

Systems Software - Utilities

Used to configure hardware e.g. scanners, printers etc.

A Printer driver formats the output for a particular printer

Translates software instructions into a format hardware can understand and vice versa

Systems Software - Drivers

Exam Revision!!! What is a device driver?

◦ A device driver is a specific type of computer software, developed to allow interaction with hardware devices. This usually constitutes an interface for communicating with the device, through the communications subsystem, providing commands to and/or receiving data from the device.

◦ It is a specialised hardware-dependent computer program, which is also operating system specific, that enables another program, typically an operating system or applications software, to interact transparently with the given device.

Systems Software – Drivers 2

the crucial point in achieving transparent interaction is the ongoing development of unconscious operations, embedded in the process of use.

Choose 3 utilities NOT listed on slide 5 and explain their function/purpose

Give two reasons why a printer driver may fail to function or function as expectedHINT: Look at slide seven

Research/Tasks

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When computer programs are written they need to be converted into machine code. This binary code is the language which the computer understands.

Compilers and Interpreters 1

SourceFile

CompilerSoftware

ExecutableFile

ExecutableFile

Output

A compiler converts the program code into machine code and saves the machine code into a file which can be executed. This program can then be transferred to other PCs and used without the need for a compiler.

Computer A

Computer B

An Interpreter works in a similar manner but code is executed straight away without being stored.

Compilers and Interpreters 2

Macros, mini programs which can record & playback keystrokes and mouse clicks in applications, are interpreted each time they are run and so need an Interpreter.

Example Exam Questions

INFO 1 Jan 10

An Operating system is the core software that allows a computer to run as a useful device.

It manages the hardware, the user interface and all other software running on the computer

Operating Systems

There are a number of Unix-like operating systems based on or descended from the Berkeley Software Distribution (BSD)

Examples

There are a number of Unix-like operating systems based on or descended from the Berkeley Software Distribution (BSD)

Examples

Today most operating systems perform the following important functions:

1. Processor management, that is, assignment of processor to different tasks being performed by the computer system.

2. Memory management, that is, allocation of main memory and other storage areas to the system programmes as well as user programmes and data.

3. Input/output management, that is, co-ordination and assignment of the different output and input device while one or more programmes are being executed.

4. File management, that is, the storage of file of various storage devices to another. It also allows all files to be easily changed and modified through the use of text editors or some other files manipulation routines.

5. Interpretation of commands and instructions.6. Coordination and assignment of compilers, assemblers, utility programs,

and other software to the various user of the computer system.7. Facilitates easy communication between the computer system and the

computer operator (human) by providing a UI that is easily accessible e.g. WIMP interface.

Functions of an Operating System

Example Exam Questions

INFO 1 Jan 11

Single Application◦ One user running one application e.g. Found on a

mobile phone, iPad etc. (ios 4 not necessarily the same now as there is multi tasking)

Multi Tasking◦ One user running many applications e.g. Personal

computers (Windows 7, Mac OSX)◦ Ram required

Single and Multi User Operating Systems

Applications Software Applications software is written to improve

our productivity i.e. it does something

It can be classified under 3 main categories:

◦ General Purpose software◦ Specialist software◦ Tailor made (bespoke) software

General Vs Specialist

General

These applications can be used for a wide variety of tasks e.g. spreadsheets can be used for accounts, sales analysis, forecasting and many others.

Specialist

This type of software lacks the flexibility of generic software and is only capable of doing a single task. Accounting software is capable of doing only accounts and so is more restrictive than a spreadsheet.

Common General Software

Generic software includes:◦ Word processing ◦ Spreadsheets ◦ Database management ◦ Graphics ◦ Desktop Publishing (DTP) ◦ Presentation◦ Web page authoring◦ Web browsing◦ Email

Word Processing Applications◦ Writing reports, memos, letter to customers

Spreadsheet Applications◦ Keeping simple company accounts, calculating employee payments, simple stock control,

modelling, simple invoice system

Database Application◦ Keeping customer records, sales records, appointments system

Desktop Publishing Application◦ Creating leaflets, posters, business cards

Presentation Software◦ Creating presentations to show customers or staff

Graphics Application◦ Manipulating images that can be used at home, school or business

Web Design (authoring) Application◦ Creating, maintaining personal or business websites

Appropriate uses of General Application Software

Word Processing Applications◦ Mail Merge, Spell Check, Find and Replace, Dictionary, Thesauraus

Spreadsheet Applications◦ Conditional Formatting, creating graphs, charts and tables, Absolute and Relative cell

referencing

Database Application◦ Reporting, sorting, filtering, querying data, Relational databases (many tables)

Desktop Publishing Application◦ Templates for popular documents, change page size and orientation, WordArt, shapes and

objects

Presentation Software◦ C

Graphics Application◦ M

Web Design (authoring) Application◦ C

Features available in General Application Software

Common Specialist Software Common specialist software include:

◦ Payroll◦ School Administration◦ Booking systems◦ Stock control/warehousing

Both generic and specialist applications can be bought bespoke or off-the-shelf

Bespoke (Custom) Software Advantages:

◦ Meets purpose exactly◦ Software will only have the features business require◦ Source code accessible for future developments

Disadvantages:◦ More expensive than off-the shelf◦ May have mistakes in code (untested) which will cost

money to correct◦ Not immediately available◦ Very limited overall backup and support – no books,

etc

Off-the-Shelf Software

Advantages:◦ Usually cheaper than custom-written ◦ Already been tested◦ Choice of brands◦ Immediately available no time delay in

implementing◦ Support from a variety of sources: e.g.

Internet sites, Books, etc.

Disadvantages:◦ Many features not required◦ Not completely suited to purpose

Integrated Package vs. Suite

Software Suite◦ Contain common productivity

tools in ONE package◦ Limited functionality◦ Usually cheaper than integrated

package◦ Often “bundled” with new PCs

Integrated Package• Separate productivity applications

that are bundled together and sold at a discount

• The applications are "integrated" i.e. have a common interface and can export/import data between apps

Open Source vs. Proprietary

Applies to all software Some software vendors /

communities licence their software as open-source

Anybody can develop the source code i.e. customise/improve the application

Often but not always free

Proprietary Software: Exclusive property of their developers

Example Exam Questions

INFO 1 Jun 09

Example Exam Questions

INFO 1 Jan 09

Example Exam Questions

INFO 1 Jan 11

Upgrading software

Overview

New software versions are released every few years by many software manufacturers

Version numbers (or years) are used to distinguish the versions

Major revisions usually labelled as integers Minor changes usually labelled as decimals

Pros/Cons

Upgrades will usually offer new functions or will be designed to make tasks easier

◦ Word 2007 puts 80% of the commonest used functions no more than two clicks away from the user after criticism that Word 2003 had too many functions (“improved” UI)

However there are technical and human considerations that the organisation needs to take into account when upgrading software

The new software may require more memory, a faster processor etc. This means that hardware needs to be upgraded (often at great expense)

Windows version

Processor Memory Hard disk

Windows 95 25 MHz 8 MB ~50 MB

Windows 98 66 MHz 24 MB 140-255 MB

Windows Millennium 150 MHz 32 MB 320 MB

Windows XP 300 MHz 128 MB 1.5 GB

Windows Vista 1 GHz 1.0 GB 15 GB

Hardware Constraints

Compatibility

The upgraded software needs to be compatible with existing systems. New versions of the software will usually open files created in older versions – backwards compatibility

The reverse isn’t always true i.e. files created in new versions may not be usable (directly) with earlier versions – downwards compatibility

Scale of upgrade

Organisations need to decide whether to upgrade some or all of their software at one time

Upgrade all

No compatibility problems

Cost issue

- Licences- Hardware upgrades

Upgrade some

Cheaper

Potential compatibility problems

Whichever option it chooses there may be some disruption associated with the changeover

Training

Upgraded software will have new features and possibly a new UI that users have to be trained to use

Organisations may also have to rewrite existing support resources (e.g. user guides)

Need?

Based on previous slides the organisation has to ask itself “Do we really need the new software?”

The technical and human constraints need to be weighed up against any potential new features/benefits the upgrade offers