Sections and Categories are completely separate from widgets.
Sections and Categories are just ways to group content in the CMS.
Sections can encompass multiple categories.
Sections:
1)Food
2)Beverage
Categories:
1)Meat Recipes
2)Salad Recipes
3)Appetizer Recipes
4)Fish Recipes
5)Alcoholic Drink Recipes
6)Non-alcoholic Drink Recipes
In the example above categories 1-4 could be linked under Section 1, while categories 5, 6 could be linked under Section 2.
Widgets are a completely separate thing:
http://www.vbulletin.com/docs/html/m...widget_manager