The list templates provided by Windows SharePoint Services are a great way to generate a list with very little effort. However, should you need to customize the templates, Windows SharePoint Services allows you to add, edit, and delete columns.
There are a plethora of column types available when you want to extend a list with an additional column. Once you name your new column, you need to select one of the column types displayed in the following table.
Most, but not all, column types have both Required and Default value options. If Required is set to true, the user must enter a value into the column when creating or editing a list item. If the user doesn’t enter a value, the Default value is used.