What Are Widgets?
Widgets are the building blocks of every Brilliant Directories website and contain the vast majority of the PHP, HTML, CSS, and JavaScript code that is used to make a website work the way it does. When customizing widget functionality, editing a widget may be required to modify many areas of a website.
Default Widgets
Default Widgets reside in a central database that all Brilliant Directories websites reference automatically. Because these widgets are always maintained in a central database, they are always automatically up-to-date.
Our internal development team regularly updates Default Widgets to maintain core functionality, add new features, and implement improvements.
If a website owner never customizes any of the Default Widgets, their website will always be automatically using the most up-to-date code.
All Default Widgets can be viewed by navigating to Toolbox » Widget Manager in the Admin area of a website:

Customized Widgets
If a Default Widget has been customized OR a new widget has been created via the New Widget button, it will appear in the "Customized Widgets" section of the Toolbox » Widget Manager page, above the Default Widgets:

Edit Widget Tabs
All widgets include four sections. The first three (HTML, CSS, JavaScript) correspond to code editing for each language depending on the selected tab.
The fourth section called Diff will highlight the difference in code between the default version of the widget vs the custom code:

Important Note: The "Diff" tab is only available for Customized Widgets.
Type of Widget
In the Edit Widget view, an additional option is available to specify the widget type:

To properly display the widget's content, select the "Widget" option. If the widget is intended to function as a banner ad, choose the "Advertisement / Banner" option instead.
Note: if ‘Advertisement / Banner’ is selected but the Display Banner Advertisements setting (Design Settings → Banner Ads) is disabled, the widget content will not be displayed.

Read More
Some useful articles related to widgets can be found below:
How To Disable/Enable A Widget
