Windows have buttons and links and lots of other widgets like checkboxes, radio buttons, lists, sliders, input fields, scroll bars, and cancel buttons.
Press buttons, for example, press an ok button.
This completes buttons.
Click on links, for example, each category in the control panel is a link.
This completes links.
Check or uncheck checkboxes, for example, the task bar has lots of checkboxes.
This completes checkboxes.
Select an option from the radio buttons, for example, select an icon size in the customize start menu.
This completes radio buttons.
Select an item in a list, for example, select a background for the desktop.
This completes lists.
Pull-down a list and select an item, for example, select a screen saver.
This completes pull-down lists.
Slide a knob to set a value, for example, turn the volume up or down.
This completes sliders.
Type into input fields, for example, change your name.
This completes input fields.
Scroll through a window like a web page in Internet Explorer.
This completes scroll bars.
Some menus have ok, apply, and cancel buttons. The apply button applies your changes and keeps the menu open. The ok button applies your changes and closes the menu. The cancel button cancels your changes and closes the menu.
For example, cancel your changes to the display properties.
This completes the cancel button.