A WikiPage is simply the basic building block of a WikiWikiWeb that contains text and images. See WikiStructures and WikiWikiWeb for more information.
A wiki page can have a substructure that includes sections for a header (for the entire wiki, or wiki groups), footer (for the entire wiki, or wiki groups), sidebars (left or right or both), and body.
An example of a wiki page structure
| Wiki header
|
Wiki sidebar 1
(optional)
| Wiki group header
| Wiki sidebar 2
(optional)
|
| Wiki page body
|
| Wiki group footer
|
| Wiki footer
|
Within the sections of a wiki page markup is used to provide formatting, layout, and if required additional structure.
See PmWiki:Special Pages for a description of Group Headers and Footers, Side bars, and other components of a wiki page.
Wiki pages can have an edit template to predefine initial content, see Cookbook:Edit Templates
Wiki pages are stored in individual flat files, see Page File Format and Flat File Advantages.