Wiki farm

A wiki farm is a website, which may or may not itself also be a wiki site, that allows for free and / or pay creation  and  of wiki.

Wiki farms vs. commercial web hosts
The structure of a  offers a 'ready-to-go' turn-key solution, which may be convenient for operators of small wiki sites with limited intentions to expand.

Advantages

 * Being as the web server and wiki software is already configured for you, you avoid the tasks of technical system administration. In some cases, this may enable you to get your initial wiki site online more quickly.  It also relieves you of the responsibility of updating the software to protect against vulnerabilities.
 * Wiki farms tend to group a large number of different wiki communities on different topics under one 'roof', which may prove to be of use in drawing traffic to a small project that might otherwise be difficult to obtain.
 * Cost often appears nominally to be lower, as the task of obtaining advertising revenue has already been handled by the wiki farm.
 * Wiki-specific technical support tends to be available, although response time may vary considerably between host providers. This is often preferred to commercial hosts, whose role is solely to provide server space; and not to support specific database (and other user software) applications (such as a wiki).
 * Some wiki farms provide automatic backup of individual wiki sites, with said backup 'dumps' available to download, store and use the file elsewhere (mirror or fork).

Limitations

 * In many cases, you are not free to switch an existing project from one  to another, or from a wiki farm to a commercial web host, without great difficulty.
 * Your project is not a separate, independent site; but merely (usually) a sub-domain of the wiki farm's main domain. This is an issue if your once-small project grows large enough to stand on its own merit.
 * Depending on the wiki farm, you may or may not be able to choose the license terms for your content. Ability to download content and database also varies widely.
 * In most cases, the choice of whether to depend on advertising revenue to fund a site, or to pay your own way is taken away from you. Where servers are funded by advertising, you have little or no control over the source or content of advertisements; some of which may be inappropriate.  This may mean that your gaming community could be sponsored by vendors of tools to cheat at those games, or that your kids-oriented site is exposed to age-inappropriate sales pitches.
 * Using a wiki farm can cost you control of your, your project, and your intellectual property. Read the fine print ; while the owners of some wiki farms talk as if the project is 'owned by the community', you may find that any domain names, project names, and logos are the property not of the individual project, but automatically become the property of the company that runs the wiki farm.  The license on the content of your wiki is also likely to be one in which the wiki farm either takes control itself, or licenses your content for commercial for-profit distribution elsewhere on the internet.  This can lead to problems where websites mirror incomplete or outdated copies of your content in order to draw traffic away from your project, and to a copy on which outside advertisers keywords, advertisements, and links have been placed.
 * In many cases, your project does not have your own user list if your wiki is one among many in a wiki farm environment. This both limits your choice (and future community members) of username (as many may already be in use elsewhere on the site), and poses an obstacle should you later wish to move your project to some other host.
 * Wiki farms typically do not provide the ability to seamlessly mix wikis with non-wiki applications, such as message boards, portals, blogs, forums, and galleries (though there are now some wiki farms which include some of these functions). The configuration is typically a predefined one used across all wiki sites on the farm, meaning this does not afford you the same levels of access to customisation as would installing the wiki software of your choice on a regular commercial wiki-capable web-host.
 * ScribbleWiki went offline without warning in early Autumn 2008, and ElWiki went down in 2007, Wikkii subsequently met a similar fate. There is absolutely no guarantee that such disasters will not recur again to other wiki farms.

Key questions to ask

 * Who owns any domain names? Can you use your own domain registration ( and keep it ), without handing over the domain ownership to the wiki farm?
 * Who owns the content? Under what license, and does that license allow unrestricted commercial use of your content by others?
 * Who owns the project name, logo, and any other identifiers? Can you be confident that the wiki farm doesn't plan to take them from you and claim ownership for them themselves?
 * What happens if you attempt to move (aka fork) your wiki project to another host? Do you have access to download both your database and your user list?  Will that original wiki farm continue to operate your old wiki site (as a 'spoon') in direct competition with your wiki site on your new provider (as Wikia have always done)?
 * What is the response time, and capacity of the server (or servers)? Wiki (and dynamic content in general) are database-intensive, leading wiki farms to often be much slower than the average for most other internet sites.
 * What is the quality of technical support? Are existing wiki farm users getting speedy resolution of any problems, or waiting months for resolution of minor issues?  As a wiki farm typically does not provide the same sysadmin-level access as an ordinary commercial web-host, you are relying on others to maintain your server for you; how do they rate?
 * Where are the backups of your project-critical data? Are you free to download a copy as a precaution, and will that copy be up-to-date and complete?
 * What software, plugins, extensions, and skins are available (if any)? If the setup is a bog-standard 'cookie-cutter' duplicate of every other wiki on the farm, is the choice of wiki software one that totally meets your needs?
 * What are the restrictions on topics or content on each site? Is the wiki farm willing to operate your wiki as you originally envisioned it, or will they reject your topic outright (or even worse, reject after you start building your content) for any number of arbitrary reasons, varying from your choice of name and license to overlap with other existing projects on the site?