-Concept Keyboard

-Speech Recognition

-Graphics Tablets

-Touch Screen

-Scanner

-Magnetic Stripe

-Smart Card

-Optical Mark Recognition

-Bar Code Reader

-Radio Frequency ID

-Magnetic Ink Characters

-Webcam

-Digital Camera

-Games Controller

Choosing a printer: Volume of output, Quality of printing, Location of printer and colour

Dot Matrix

Inkjet Printer

Laser Printer

-Plotter

-Screens

-Speakers

-Secondary Storage - more permanent, non volatile.

Flash Memory

Hard Disks

Magnetic Tape

Optical Storage (CD-R (Recordable), CD-RW (Rewritable), DVD-R (Recordable), DVD-RW (Rewritable), DVD-ROM (Rewritable), DVD BD R (Recordable), DVD BR RW (Rewritable))

Online  Storage

E.g. Hard Disk. High storage capacity and most desktops and laptops have one as standard.

-Removable Storage

You must consider:

• Volume of data to be stored
• Reason data is being stored
• Whether data will need to be rewritten
• Speed of recovery
• Physical size of device

-Archive Storage

Data may need to be stored offline, e.g. storing accounts from previous financial years somewhere else than a computer, or storing a film collection. Typically you would use an optical disk for this but other media such as flash memory or and external hard disk may be used.

-Transferring Files

You can use:

• Optical Discs
• Flash Memory
• Email
• External Hard Disk

-System Software: used to manage the hardware and software resources of a computer

Utility Programs: these perform useful tasks for users:

• Firewall
• Anti-virus
• Compression (zip)
• Disk Defragmentation
• Disk Clean Up
• Backup
• Scan Disk
• Screensavers

Translators: Compilers and Interpreters translate programs written in a high level language, such as: VB, Pascal, C or Delphi into machine code. Assemblers translate a program written in a low level language into machine code.

Library Code: Previously written program code available from 3rd parties. They can be incorporated into current or future developments and can be used by many applications.

-Desktop Publishing e.g. MS publisher

-Graphics Packages:

Bitmap, e.g. MS Paint

Vector, e.g. Adobe Illustrator, Corel Draw

-Sound

Sampling Rate - frequency at which samples are taken

Sampling Resolution - number of bits used to store one sound sample

-Spreadsheets e.g. MS Excel

-Presentation Graphics Software e.g. MS PowerPoint

-Web Authoring Software

-Web Browsers e.g. IE, Firefox

-Electronic Mail

-Common computer health problems

• Stress

-People feeling they are unable to keep up with work or keep up with younger workers

-Modern workers find it difficult to escape work.

-Lot of work having to be done when returning from a holidays.

-Not uncommon for employees who are being monitored via audit software to develop headaches and stress.

• RSI

-Numbness or tingling in arms or hands.

-Aching or stiffness in arms, necks or shoulders.

-Serious back problems for stopping people lifting objects.

-RSI often reoccurs after first occurrence.

• Backache
• Eyestrain

-Glare

-Improper lighting

-Poor work practices

-Poorly designed workstaions

Measures to protect health when using computers

-Take regular breaks to prevent eye strain/hedaches

-Adjust chair height to avoid backache

-Adjust height of top of monitor so at eye level

-Use wrist pad to relieve RSI when using mouse or keyboard.

• Perform an analysis of workstations

• Provide tiltable screens

• Provide anti-glare screen filters

• Provide adjustable chairs

• Provide foot supports

• Make sure lighting is suitable

• Make sure workstations are not cramped

• Provide training to employees in the use of workstations

• Ensure employees take regular breaks or changes in activity

• Provide regular eye tests for workstation users

EMPLOYEE'S RESPONSIBILTIES

• Take reasonable care of the health and safety of themselves and of others who may be affected by what they do or don’t do

• Follow instructions from the employer on health and safety matters and attend relevant health and safety training

• Report hazards and defects observed in the workplace

• Do not misuse any equipment that is provided for safety purposes

User - person who will administer the system. This may involve altering input, updating content and using the output in some way.

Audience - person or people who the system is aimed at.

Identifying what the problem is, in order to do this a number of steps needs to be followed:

• Identify the problem
• Identify the client, user and audience
• Identify user skill level
• Gather information
• Interview: time consuming but most effective
• Questionnaire: quick to gather information and can be sent to many people but difficult to get quality information
• Study existing paperwork: look closely at current manuals and reference documents that are currently used to find out more information
• Observation: watch how the current system is used. This will give you useful insight into where problems occur
• Produce the requirements (SMART)
• Identify input, process and output

Process: design of what processing needs to be performed

Output: design of the output

Input

Ensuring data is entered accurately and efficiently. Barcode readers and OMR are very useful.

Validation - process of checking whether data is sensible or reasonable on input

Presence - checks fields to make sure data is present

Format - checks the data is in the correct format, e.g. code may have a pattern of 2 letters than 4 numbers

Range - checks the data is within a given range

Length - checks the data entered is the correct length

Look up - if a customer has filled in a customer number, the computer can look up this in their file and display the name and address.

List - the operator chooses from a list of valid values

Cross field - makes sure two fields are always entered correctly. e.g. if a certain phone contract is only available on a  certain network, it will be rejected if a different network is entered

Check digit -complex calculation performed on an ISBN number. Result of the calculation is then added to the end of the original ISBN number. The calculation is repeated and if the result is different, an error has occurred.

Verification - process of checking by comparison that no alterations are made to data when entered, e.g. entering data twice, with the 2nd entry compared to the 1st to ensure accuracy, such as when setting  a password.

Data Capture Forms - Can be on the computer, validated then if done on a computer, if done by hand, data has to be transferred to a computer at a later stage which takes a long time.

Designing the User Interface - Needs to be carefully planned, the requirements give you a clear idea of what to do

Output

The  user interface  may  include screen  based,  paper based  and  sound outputs. Make sure you test the output on the same equipment that the user will be using. Printed output may have to fit in with a particular house style for that company or organisation.

Test Planning

At this stage you should be planning how to test that your system works effectively. The actual Testing stage comes later. At this point you should also check that your user is happy with all the Designs!

This involves building the system. It is very important that the overall tasks are broken down into sub tasks and that you carefully plan when these sub tasks will be implemented. Each stage of the implementation should be documented as this will greatly assist any future work you do. Annotated screenshots are one of the best methods for this.

Validity of input

Ensures that data entered is reasonable.

Boundary Data: on the limits of acceptability

Erroneous Data: should not be accepted

Typical Data: should be accepted 

Accuracy of output

it's very important that the system produces accurate results, e.g. test to make sure that the system completed calculations correctly or that a web page takes you to a certain page when a certain hyperlink is clicked.

Presentation of output

How the output is presented and how the system looks must be tested. e.g. on screen forms must be thoroughly tested to ensure data is displayed properly and that the user can use the system in a logical manner or a printed invoice has all the correct details on it and they all fit onto one page.

• Initial user requirements

• Comments on how well you have achieved each
  requirement

• Limitations of your system

• Suggestions for improvements

Questions to ask yourself when evaluating a system:

• Does the solution do what it was supposed to do?

• Does it do it in the way it was supposed to do it?

• Is the solution an effective one? If not, how could it be made effective?

• How efficient are the controls?

• How intuitive is the solution?

• How accurate is the input data?

• How efficient is the processing?

• How appropriate are the outputs?

• How robust is the solution?