Optional advanced feature
You can assign a variable a specific name in the query template editor. This is especially useful when dealing with a large number of variables. This feature is only visible to you in the builder in your widget's query template code.

The widget builder will automatically pull in the part of your query that came before the variable as the plain text label before each component on the widget. You can edit this text label to be anything you want.

In Input Fields, the default value will be pre-filled text in the input box. For radio buttons and checkboxes, the default value will be text next to the radio button and checkbox. For popup menus, the default text will be the first option in the list.

You can choose to turn your variable into a text input field, popup menu, radio button, or checkbox. You can add additional popup menu options and radio button selections in step 2.

Optional advanced feature
Choosing an interpretation can help with disambiguation if your widget's query contains elements that have multiple meanings, which generate assumptions in Wolfram|Alpha.