# Available Lists

There are several different types of lists in Paligo. Some of the most common are:

• itemizedlist

• orderedlist

• procedure

• simplelist: a list without bullets or numbers. It also has some features like being able to display it horizontally, in several columns, etc.

• variablelist: a list of terms and definitions.

• calloutlist: a list of callouts for code listings (programlisting and similar elements)

## itemizedlist

itemizedlist — A list in which each entry is marked with a bullet or similar symbol. An itemizedlist is also often called "bullet list" or "unordered list".

##### Description

In an itemizedlist, each item of the list is marked with a bullet, dash, or other symbol.

##### Parents

Can be used in most block elements.

##### Children

The main child element is listitem. At the top of an itemizedlist many other elements can be used, however, as in an introduction to the itemizedlist, including an (optional) titlepara, and more.

Example 1. Itemizedlist
<itemizedlist>
<para>List of tools:</para>
<listitem>
<para>Hammer</para>
</listitem>
<listitem>
<para>Screwdriver</para>
</listitem>
<listitem>
<para>Drill</para>
</listitem>
</itemizedlist>

## orderedlist

orderedlist — A numbered list. This should usually be distinguished from a procedure, which is used for instructions/tasks.

##### Description

In an orderedlist, each member of the list is marked with a numeral, letter, or other sequential symbol (such as roman numerals).

##### Parents

Can be used in most block elements.

##### Children

The main child element is listitem. At the top of an orderedlist many other elements can be used, however, as in an introduction to the orderedlist, including an (optional) titlepara, and more.

Example 2. Orderedlist
<orderedlist>
<para>List of tools:</para>
<listitem>
<para>Hammer</para>
</listitem>
<listitem>
<para>Screwdriver</para>
</listitem>
<listitem>
<para>Drill</para>
</listitem>
</orderedlist>

## procedure

procedure — A list of operations to be performed in a well-defined sequence

##### Description

A procedure is used to write an instruction or a task made up of steps (and possibly, substep)s. In most cases it is recommended to use the procedure list type rather than a regular orderedlist for instructions, as it provides several benefits to distinguish between them.

There are no explicit elements for pre- and post-conditions (sometimes called pre-requisites or post-requisites) in the procedure  element in Paligo, just as in DocBook. The model is intentionally simpler, and such elements are avoided. (See this article for more on this: There are no Prerequisites). Instead, they should be described as steps (check the pre-conditions in the first step and the results in the last step).

(If still really desired, the task element, provides some of this infrastructure, but there is little out-of-the-box styling support for this and it may require a customization.)

##### Parents

The procedure element is most often used as a direct child to section (i.e the root element of a topic). But it is also valid in many other contexts, so you could for example have a procedure in a table cell, in an example, etc. See the full list of parents here.

##### Children

The main child element is step. At the top of a procedure many other elements can be used, however, as in an introduction to the procedure, including an (optional) titlepara, and more.

Example 3. Procedure
<procedure>
<title>An Example Procedure</title>
<step>
<para> A Step </para>
</step>
<step>
<para> Another Step </para>
<substeps>
<step>
<para> Substeps can be nested indefinitely deep. </para>
</step>
</substeps>
</step>
<step>
<para> A Final Step </para>
</step>
</procedure>