# DD - Definition Description

Syntax | <DD>...</DD>
Attribute Specifications | common attributes
Contents | Inline elements, block-level elements
Contained in | DL

The DD element provides the definition of a term in a definition list. The closing tag for DD is optional, but its use prevents common browser bugs with style sheets.

DD may contain block-level elements such as P, H2, TABLE, and DL. This allows definition lists to be nested, as in the following example:

    <DL>

      <DT><A NAME="spanning-tree">Spanning tree</A></DT>
      <DD>
        <P>
          A spanning tree of a graph is a <A HREF="#tree">tree</A>
          that contains all the vertices of the graph. There are two
          main types of spanning trees:
        </P>

        <DL>
          <DT>BFS spanning tree</DT>
          <DD>
            A spanning tree formed by a breadth-first search on the graph.
          </DD>
          <DT>DFS spanning tree</DT>
          <DD>
            A spanning tree formed by a depth-first search on the graph.
          </DD>
        </DL>
      </DD>

      <DT><A NAME=tree>Tree</A></DT>
      <DD>
        <P>
          A tree is a connected, undirected graph without cycles.
        </P>
      </DD>

    </DL>

A DD element should generally be preceded by a DT element that gives the term defined by the DD. A single definition term may have multiple definitions associated with it, and a single definition may have multiple terms.

## More Information

- DD in W3C HTML 4.0 Recommendation
- DD in W3C HTML 3.2 Recommendation
- DD in HTML 2.0 Standard
- DD in WDG HTML 3.2 Reference
- DD in Learning HTML 3.2 by Examples