Describe the various operable controls.

Operable controls are elements in a user interface that allow users to input, select, modify, or execute commands.

1. Buttons:
   • Appearance: Rectangular with text indicating an action.
   • Function: When clicked, immediately performs the described action.
2. Text Entry/Read-only Controls:
   • Type: Fields where text is entered or modified through the keyboard.
   • Use: Entering information or displaying read-only text.
3. Selection Controls:
   • Purpose: Display all possible options or choices for a property.
   • Interaction: Users choose from displayed options, sometimes involving scrolling.
   • Examples: Radio buttons, check boxes, list boxes, drop-down menus.
4. Combination Entry/Selection Controls:
   • Nature: Combines characteristics of both text and selection fields.
   • Use: Allows users to type information or select from a predefined list.
   • Examples: Spin boxes, attached combination boxes, drop-down menus.