This annotation is used to create a bulleted list of items. A bulleted list is a collection of items placed in no specific order. The parentheses must contain a number that corresponds to the nesting level of the list item. Unordered lists can be as deeply nested as you want.
The character at the beginning of the list will sometimes be a bullet, sometimes a dash, and sometimes it is some other character. That is dependent on the style of the author and, sometimes, on the nesting level of the list item.
Here is a bulleted list with two nesting levels.
This will require two rules, one for each nesting level.
This is the output you may get from these rules.