There's a tool that turns your Web browser into a time machine, and librarians at Stanford University have figured out how to use it.

In honor of the 25th anniversary of the World Wide Web this year, Stanford created a digital archive of its bygone Web pages, some of which were among the earliest pages ever published on the Web. Known as the Stanford Wayback, the tool is a customized version of an open-source platform — the Wayback Machine — developed by the nonprofit group Internet Archive.

Among other sites, the new digital archive is home to the SLAC National Accelerator Laboratory site, which was originally created in 1991 and is the earliest known website in the United States, according to Stanford. [Top 10 Inventions That Changed the World]

"Thankfully, a handful of staff at SLAC who worked on the early Web fortuitously saved the files, along with their time stamps, associated with the first and several subsequent versions of their website," Nicholas Taylor, a Web archiving service manager for Stanford Libraries, said in a statement.

The Stanford Wayback includes a set of featured archived sites, and users can see what SLAC's website looked like in 1995 compared with its updated (but still very '90s-style) home page in 1999. Users can also search through about 435 billion other archived Web pages that are on the original Wayback Machine.

While people could probably spend all day looking nostalgically at old websites and swooning over the early days of the Web, the Wayback Machine (both the original and Stanford's version) serve a greater purpose, as well. Stanford's digital archive is part of a larger, universitywide Web archiving initiative, which aims to preserve and provide access to Web content that's at risk of being updated, replaced or lost. The project focuses on archiving websites that could be used for research and as teaching resources in the future. This includes government websites from around the world, digital game sites and social media pages, according to Stanford.

"The early pages of the Web may seem rudimentary and visually dull to today's user; however, they offer great insight into Web history, functionality, changes and trends," Taylor said.

One of the projects currently underway as a part of this initiative is a comprehensive archive of all the websites for the 2014 congressional primary and general-election candidates. The Stanford Library is working on the project with Archive-It (a subscription digital archiving service) and Stanford's Institute for Research in the Social Sciences (IRiSS).

The Stanford Library is also integrating its digital archive into its regular online catalog. This will enable students to search both current sites and those that have been archived.

"A good portion of today's information is being published online, as ephemeral Web pages. In order to fulfill our mission, it is imperative that we curate and make accessible for current and future generations Web-based content on topics that matter to our community," said Michael Keller, Stanford's university librarian.

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