Class 10 IT 402 – Revision Notes
Web Application and Security
Computer Accessibility
Computer Accessibility refers to the user-friendliness of a computer system for all, regardless of their disability. it enables a person with a disability or impairment to use a computer. It is known as Assistive Technology. There are numerous types of impairment that impact computer usage. These include:
- Cognitive impairments and learning disabilities
- Attention Deficit Hyperactivity Disorder (ADHD) or autism.
- Visual impairment.
- Hearing impairment
- Motor impairment
Launching Accessibility Options:
To launch accessibility options in WindowsXP, Click Start > Control Panel > Accessibility Options.
Various tabs in the Accessibility Option Window:
Keyboard Tab to configure accessibility options for the Keyboard is displayed
1) Sticky Keys: Sticky Keys is an accessibility feature to help computer users with physical disabilities, but it is also used by others as a means to reduce repetitive strain.
StickyKeys allows the user to press and release a modifier key, such as Shift, Ctrl, Alt, or the Windows key, and have it remain active until any other key is pressed.
- To enable StickyKeys, select Use StickyKeys.
- Click Apply.
- Click OK.
The Sticky Keys icon appears in the system tray.
2) Filter Keys: Filter Keys are a feature of Microsoft Windows. It is an accessibility function that tells the keyboard to ignore brief or repeated keystrokes, making typing easier for people with hand
tremors.
• To enable Filter Keys, check Use Filter Keys.
• Click Settings under Filter Keys and check “Ignore Repeated Keystrokes”.
• Click Apply.
• Click OK.
The FilterKeys icon appears in the system tray
3) ToggleKeys: ToggleKeys is an accessibility function that is designed for people who have vision impairment or cognitive disabilities. When ToggleKeys is turned on, the computer emits sound cues when the locking keys (Caps Lock, Num Lock, or Scroll Lock) are pressed.
A high sound is emitted when the keys are switched on and a low sound is emitted when they are switched off.
- To enable ToggleKeys, Check Use ToggleKeys.
- Click Settings under ToggleKeys. • Click Apply
- Click OK.
Having enabled ToggleKeys, you can see its effect by any one of the following keys NUM LOCK, CAPS LOCK or SCROLL LOCK. Notice that on doing so, you hear a beep.
Sound Tab to configure accessibility options for sound is displayed.
1) SoundSentry: SoundSentry is designed to help users with auditory impairments. SoundSentry generates visual warnings, such as a blinking title bar or a flashing border, whenever the computer generates a sound.
• To enable SoundSentry, Check Use SoundSentry under Sound Tab. Doing so activates a drop-down list wherefrom you can choose the type of visual warning desired.
• Click Apply.
• Click OK.
2) ShowSounds: ShowSounds instructs applications that convey information by sound, to also provide information visually, through text captions or informative icons.
• To enable ShowSounds, Check Use ShowSounds under Sound Tab.
• Click Apply.
• Click OK
Display Tab to configure accessibility options for Display is displayed.
1) High Contrast: High Contrast is an accessibility feature to assist people with vision impairment. You can change the size and color of fonts and the background for ease of viewing.
• To enable HighContrast, Check Use HighContrast
• Under Display Tab (figure 5).
• Click Apply.
• Click OK.
2) Cursor Options: Cursor Options is also an accessibility feature that assists people with vision impairment by changing the blink rate and width of the cursor.
• To change the speed of the cursor blink, move the Blink Rate slider back and forth. Notice the cursor blinking at various speeds.
• To change the width of the cursor, move the Width slider back and forth. Notice the with of the cursor changing.
Mouse Tab to configure accessibility options for Mouse is displayed.
1) MouseKeys: MouseKeys is an accessibility feature that assists people who have difficulty using a mouse. This option uses the keyboard (especially numeric keypad) as a pointing device instead of a mouse.
• To enable MouseKeys, Check Use MouseKeys.
• Click Apply.
• Click OK.
General Tab enables you to configure accessibility options for all users.
1) Serial Keys: Serial Keys is an accessibility feature that assists people that have difficulty using a keyboard or a mouse (or both). They can use special devices such as Sip, Puff and Breath Switches to provide input to the computer through Serial Ports.
