Wikipedia has millions of articles across numerous languages, and that makes it a pain to ensure the links to third-party sites are up to date, if they can work at all. What are you supposed to do if an important reference stops working? You can relax, it seems -- the Internet Archive has 'rescued' 9 million previously broken Wikipedia links by caching them in the Wayback Machine and other archive services. The team accomplished the feat by using a bot to search for broken links in articles and automatically restore those links with archived versions.
The Internet Archive plans further action, too. It's promising to check more Wikipedia versions and speed up its ability to fix links. You'll also see it investigate the use of this process for other media, such as e-books and academic papers, and test methods that encourage writers to use links to archives instead of live sites.
This may be more important than it seems at first blush. It's a helpful way of preserving internet history, but it also boosts the credibility of Wikipedia as a whole. You don't know if a reference is accurate unless you can read the source, and you can now do that even if the source has long since vanished. This could be especially vital for students who use Wikipedia as a starting point and need to cite original articles in their reports.