Using Standards, Guidelines and Tools.

State transition networks (STNs) are used for dialog descriptions. The STNs can be presented in several ways and it is up to a developer to understand and design a consistent, predictable and forgiving interface. Depending on user preferences, understanding and knowledge the designer should make a choice to use the most desired interface to ensure smooth HCI.

Menus
The types of menus are a pull-down menu, cascaded menu, and pop-up menu. Menus are widely used in common interfaces in PC, desktop workstations, Microsoft Windows, MacOs and various Windows0- based systems for Unix. They are usually attached to the menu bar near the top of a window. A menu bar usually contains a single word, which leads to pull-down menus.
Advantages:
• Save the screen space to display more functions and content
• Are visible and easy to access
• Allow the cursor to wrap at the top and bottom of a menu
• Provide guiding principle on available and unavailable-state emphasis on action and settings choices that can be or cannot be selected in the current context
• Hierarchical elements create submenus that are displayed in logical order to perform different tasks
• Allow the designer to add many items in the submenu and group them in logical clusters
• Provide additional information such as keyboard shortcuts
Disadvantages
• Menus work differently in MacOs and Microsoft Windows environments
• Menus can become long and disorganized by creating cascading submenus
• Once the submenus are extended, they become difficult to navigate and the user can easily be confused and lost in performing any desired task
• Require some expertise with computers and windows display
• Menus are used with a pointing device such as mouse and can become difficult to use for people with lack of movable abilities and precise coordination (elderly people, neurological infirmity such as Multiple Sclerosis, etc.)

Controls
Controls are incorporated into a design as a visual- interface to allow a user to select choices and to type information. Controls can incorporate a few different elements: Check boxes, Radio buttons, Drop-down lists, and List boxes. List boxes and Drop- down lists are allowing a user to select an option from the existing values and they not allow the user to input their own information. Each control or field of controls has to be identified by the title or the descriptive name to indicate the control’s function. Controls should be consistent in look-and-feel and it is best practice to use the ones that are provided by the operating environment.
Advantages
• Allow users to make a few selections within one visual interface and are easy to navigate
• Controls provide the scope of information within one visual interface which helps users to control their preferences at once
• The size of Controls windows can be adjusted as needed
• Users can easily recover their actions if any mistakes were done (high recoverability) by opening the controls and inspecting their selections
• Allow users to cancel their selection by pressing the CANCEL Push Button
• Controls display Help button that allows easy access to more information
Disadvantages
• Controls take a large amount of the screen space
• Can require some level of expertise from the user if the labels of control’s function are not clearly identified or placed
• Check boxes and Radio boxes can be confusing if the user is not familiar with their performances
• Controls require the user to confirm their selection by clicking on the OK

Push Button
Designer should be familiar with various components that would allow users to perform different tasks. By assessing advantages and disadvantages of them, HCI can become consistent, predictable and forgiving. Components should be consistent, simple, provide needed support and responsive.


References
Dix, A., Finlay, J., Abowd, G. & Beale, R. (1998). Human- Computer Interaction. Prentice Hall Europe.
ISII GUI Style Guide (1999). Retrieved October 22, 2008 from, http://www.isii.com/style_guide/style_guide.html