|Have you checked your lynx?|
This week my Adult Learning class was asked to post links to metasites that list useful Web 2.0 tools. (A metasite is a site that directs users to other sites.) One of the criteria was that the metasites not be more than two years old. Our instructor specified this partly because, at the hyperspace pace of the web, tools seem to come and go at warp speed. But also, it's rare that even well-maintained sites can keep all their links current. The longer the site is up, the greater the chance it will experience "link rot," or the presence of links that return a 404 error or otherwise no longer reach their intended target.
How serious is the problem? National Public Radio's Stopping Link Rot notes that "half of the links were dead already in Supreme Court opinions." They report that for the Harvard Law Review, 70 percent of the links were dead. The content the links go to can also be changed, which might mislead users who click on the links. This could have serious consequences not only for law, but for fields like medicine.
The situation is equally grave in the sciences: According to the website Journalists' Resource, one study showed the average lifespan of a hyperlink in scientific articles was 9. 3 years, yet only 63 percent of the articles had been archived.
How do you combat this insidious rot that turns away users and lessons the value of your page? "The Growing Problem of Internet "Link Rot" and Best Practices for Online and Media Publishers" gives extensive guidelines for preventing link rot. On their own site, which has over 10,000 links, Journalists' Resource says 10 or more links a week break. Links for academic articles fare no better.
A casual blogger is not likely to run a plug-in, WordPress extension or other bad-link-detecting aid, but we can still adopt some of the best practices that Journalists' Resource recommends:
- Add only essential links. The fewer links you have, the less likely they are to break.
- Keep links clearly visible, linking text of two to five words and distinguishing them by color and style. Avoid linking longer and one-word texts.
- Make sure the text you are linking clearly indicates what the user will find if she clicks. Don't use URLs, or words like "this link," "click here" and so on. Don't "stack" links, placing them one after another in a sentence with no break in between. Consider using hover text that appears when readers mouse over, but do it consistently if you opt for this method.
- Whenever possible, link to stable URLs and link to reliable sites that are not likely to change. Established databases at universities and government agencies, academic papers with DOI (digital object identifier) numbers, perma.cc (a service that archives content and assures link stability) WebCite (an on-demand archiving service) and permalinks rather than shortlinks are good choices.
- Journalists' Resource recommends whenever possible linking to web pages rather than pdfs.
- Try to look for a "clean" URL that is stable with no extra characters. URLS with ?, % and other symbols can be problematic, and the longer the URL the greater the chance it will go bad.
- Avoid link shorteners (bit.ly, tinyurl) unless you are tweeting.
- Don't link through paywalls or in ways that could violate copyright.
- Check your links after you post and again from time to time. If you publish on the web a lot, use plug-ins, extensions, or other tools that check links automatically.
- Prevent your website from contributing to link rot by using URLs with safe characters, creating landing pages for .pdfs that you post, and set up redirect pages when you change the organization of your site.
(See more tips and details at Journalists' Resource's best practices article.)
Taking the health of your links seriously is one of the steps toward taking your own content seriously. Be considerate of people who visit your site, and protect your reputation, by ensuring the content you link to will be available for users who may depend on it.