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The Library of Congress > Digital Preservation > News Archive > Web Browser Supports Time Travel

September 24, 2010 -- For those who use the Mozilla Firefox browser, you now have the option to time travel through the web.  MementoFox (external link) is a free extension that users can add-on to their browsers.

The extension implements the Memento protocal (external link), which the Los Alamos National Laboratory and Old Dominion University are developing to enable capture of and access to older versions of websites. 

Screenshots of from 2007 (top) and 2010 (bottom) using the MementoFox plugin.

Screenshots of from 2007 (top) and 2010 (bottom) using the MementoFox plugin.

Memento allows a user to link resources, or web pages, with their previous versions automatically.  The term Memento refers to an archival record of a resource as well as the technological framework that supports the ability to discover and browse older versions of Web resources. 

One of the challenges of researching older versions of Internet resources is searching for them in web archives. With the Firefox add-on, users can easily view older versions in the same browser without having to search across archives.

After a URL is specified in the browser, the newly released extension allows users to set a target day, using the slider bar (the "add-on").  The protocol will search archives across the web for previous versions of the URL.   As long as those archives are available on a server accessible across the web, MementoFox will return the previous targeted version.

MementoFox is available for download (external link) and developers interested in working with the protocol can join the development group (external link).

The Memento project receives support from the Library of Congress National Digital Information Infrastructure and Preservation Program.