There are two kinds of wiki modes:
Wiki modes to edit pages on a remote wiki:
curlto download and post pages
Wiki modes to edit pages on a local wiki:
Wiki modes to edit text files that might eventually end up on a wiki (usually a mode to use when Emacs acts as the external editor to a browser):
Raw wiki browsers – view and edit a wiki on a remote server without a web browser:
Traditionally, a wiki is an application running on the web somewhere, a CGI script, a JSP, whatever. This wiki has its page database stored on the server, often in cryptic formats, perhaps using version control. Here, we call this a “remote” wiki. All wikis using the Usemod script (such as this one) are therefore “remote” wikis.
People have written modes to edit such a remote wiki: These modes will query for a server and a file, fetch the file, allow you to edit it within Emacs, and save it back to the server.
What characterizes a wiki, though, is something else (the definition varies a lot). Some people claim that the two core features are automatic linking (using a special naming convention) and editability. These features, however, can be implemented in Emacs as well! That is what a wiki mode does. The wiki mode is just another mode in Emacs that allows you to edit text, and it does automatic linking based on a special naming convention. Since these text files usually exist locally, we call this a “local” wiki. It is usually not served to other people on the web, although it may be shared with other people via a file share (or an FTP server).
The modes used to edit local wikis usually allow you to convert your collection of text files to HTML, and some even use the httpd.el package to let Emacs act as a web server.
Note that the wiki software written in Perl known as “Oddmuse” is separate and distinct from “EmacsMuse”, aka “Muse mode” or just “Muse”. This site (the Emacs Wiki) runs on Oddmuse. As mentioned above, there’s an Oddmuse mode for use with Oddmuse wiki’s.
Also note that, although Emacs Muse was forked off of Emacs Wiki Mode (in 2004), the two are no longer the same. Neither depends upon the other. When Muse 3.03 is released, it will be considered a complete replacement for Emacs Wiki Mode.
Finally, emacs-wiki.el refers to Emacs Wiki Mode, and wiki.el refers to the (now abandoned) “Wiki Mode”.