|Syntax and mark-up / Lists|
There are four semantically-distinct general purpose list types in DITA, each of which is typically rendered differently in the output.
These lists are semantically distinct, although the difference between a simple list and an unordered list is minor. Some processors may output simple lists as inline lists, rather than block lists (separate lines per item).
List types are not interchangeable; the content of the list will determine which list type is appropriate for it. Choose a list type by considering the nature of the list, not by the way you think the list will be rendered in the output.
The difference between simple and unordered lists
The difference between definition and unordered lists
Although simple lists are technically valid inside ordered, unordered and definition list items, you should avoid nesting simple lists inside other lists.
DITA includes some other special purpose list structures, such as parameter list (parml) and choice list (choices).