When we should use <dl> over <ul>?

Question

In what scenarios we should go for <dl> not <ul>?

Does it matter for screen reader user <ul> or <dl>? does screen reader software notify user about content is in <ul> or <dl>?

Answer 1

A <dl> is a definition list. It should be used in such a case as, perhaps, a dictionary:

Use-case:

<dl> <dt>Thesaurus</dt> <dd>A book for finding synonyms of other words, often alphabetical. Similar to a dictionary.</dd> </dl> 

Result of the above:

Thesaurus

A book for finding synonyms of other words, often alphabetical. Similar to a dictionary.

---

The idea being that the term-to-be-defined is held in the <dt> element, and the definition of that term is given in the <dd>.

A <ul> is an unordered list. Now, a <dl> does not imply any order to its contents, but it does imply a semantic relation between its children. A <ul>, however, could contain anything that is not ordered.

Answer 2

When you're working with a set of definitions and not merely an list of unordered items.