Out of the box Sputnik behaves like a wiki with all the standard wiki features:
editable pages, mild and non-invasive protection against spam bots, history view of
pages, diff, preview, per-page-RSS feed for site changes.
A basic Sputnik installation consists of just a few source files that add
up to less than 2000 lines of code. Sputnik based upon software provided by the
Kepler project, such as WSAPI
and LuaRocks, and can thus run on a wide range of web servers.

At the same time, Sputnik is designed to be used as a platform for a wide range of “social software” applications. A simple change of templates and perhaps a few lines of Lua code can turn it into a photo album, a blog, a calendar, a mailing list viewer, or almost anything else. So, you can think of it as a web platform of sorts. In addition to allowing you to add custom bells and whistles to a wiki, Sputnik provides a good foundation for anything that’s kind of like a wiki but not quite. Sputnik stores its data as versioned “nodes” that can be editable through the web (just like any wiki). However, it allows those pages to store any data that can be saved as text (prose, comma-separated values, lists of named parameters, Lua tables, mbox-formatted messages, XML, etc.) While by default the page is displayed as if it carried Markdown-formatted text, the way the page is viewed (or edited, or saved, etc.) can be overriden on a per-page basis.