Creators of Web content often are faced with linkrot, which is the problem of a URL changing or expiring, and causing the Webpage to break.
People have suggested caching servers, durable URLs and permalinks to circumvent this problem.
Although I am not fully convinced, in some ways, that's a problem the emerging Digital Object Identifier (DOI) standard will solve.
DOIs also have the advantage that the URLs are shorter and very specific.
Like the competing OpenURL standard (see my review "Problem with OpenURLs"), DOI has numerous applications in scholarly publishing, in electronic aggregations, electronic libraries, and digital archiving.
Example:
Let's say you want to link to my article in ACM Software Engineering Notes. The actual URL is something like
Now who can remember that URL ?!
Whereas using DOI, the URL is simply: http://doi.acm.org/10.1145/126496.126501 and is typically guaranteed to be durable even if the website changes its underlying technologies (from CFM to ASP to ASPX or JSP).
See: My other blog entries on Library Technologies
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