Different External Links

This wiki feature displays external links differently than internal links (or other links like InterWiki InterLinks).

Possibilities

All of the differences described here can be implemented by using CSS to style links; the WikiEngine would just need to classify links and indicate the link type in the anchor element, probably using a class attribute, but possibly using the rel attribute.

Implemented

• Most wikis do not display different link colors for external links vs. internal links.
• Some use a small icon in front of the link.
• Some use a small icon after the link.
• A few use tool tips such that when your mouse hovers over the link you can see that it is an external link as opposed to an internal link.

Unimplemented

• It is possible to display the link color differently for external links vs internal links. Don’t know of any wikis that do so, but I’ve seen it someplace. Today I saw 4 different colors of links on one wiki page. (I think half of those colors are for the “visited” version of the other half).
• It is also possible to have a different underline type for external links.
• Presumably the font could be different as well, but I’ve not seen any that do that.
• Even more flavors of links: internal, near, interwiki, on-this-server(but not a normal wiki page), and external.

Implementations

MoinMoin uses a small icon before the link, compatible with their InterLink icons, for external links:

TracWiki also uses a small icon, but doesn’t have differentiated InterLink icons:

MediaWiki uses a small icon after the link, for external links, but doesn’t have differentiated InterLink icons:

JspWiki also uses a small icon after the link, for external links, and also doesn’t have differentiated InterLink icons:

With SocialText both links look the same, but a tooltip is displayed if your cursor hovers over the link:

From the wikiengine programmer point of view, there are 2 ways to implement DifferentExternalLinks:

• in the served HTML page, make external links something like <a class="external" href="..." >...</a>. Then put the precise description of its appearance in the CSS file.
• in the served HTML pages, insert several copies of the precise description, one for each external link.

Both ways look the same to normal readers, and can implement any of the appearances described below.

Is it possible to use ordinary links <a href="..." >...</a>, and have CSS mark the links up differently? Is there any way for CSS to distinguish a link that starts with http:// (an “absolute” link to an external site) from a link that does not (a “relative” link to the same site)?

Activity

Terminology

Problems

• Icons with links an be distracting.
• TracWiki address this by using a very ‘soft’ icon.
• MediaWiki addresses this by putting the icon after the link
• Icons may conflict with InterLink.
• Tooltips are not obvious enough, most people will click before they see the tooltip for a link.
• Complexity. Some simpler solutions:
• simply display the raw URL for external links (rather than having special mark-up to hide it and substitute link text). (CommunityWiki:VisibleMarkup )
• community solution on some wiki (such as Wikipedia): editors are expected to move all external URLs to a special “External Links” section of the page.
• community solution on other wiki: editors are supposed to make internal links look like a word or phrase, external links have a “:” colon in them.

See Also

InterLink, NearLink, UseMod:WikiPatches/InterSiteIcons

Contributors

ChristopherAllen

CategoryFeature CategoryLinking