Memento: An RFC and a Chrome Plugin

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A belated congratulations to the Memento team on the publication of their RFC and Google Chrome plugin for the Memento WWW time travel protocol. A fan of the Internet Archive Wayback Machine? Ever look at the history of a Wikipedia page? Curious to know about changes to a particular web page? The first is now easier to access...the second is a work in progress...and the third may come to a website near you. See what I mean through this demonstration video.

If you want to see more of the details, check out the guided introduction. If you are a hardcore techie, take a look at the text of RFC 7089. If you'd like to try it out yourself, load up Chrome and install the Memento extension. Because the Chrome Web Store won't let you see the details of an extension unless you are actually using Chrome, I've reproduced the description here:

Travel to the past of the web by right-clicking pages and links.

Memento for Chrome allows you to seamlessly navigate between the present web and the web of the past. It turns your browser into a web time travel machine that is activated by means of a Memento sub-menu that is available on right-click.

First, select a date for time travel by clicking the black Memento extension icon. Now right-click on a web page, and click the "Get near …" option from the Memento sub-menu to see what the page looked like around the selected date. Do the same for any link in a page to see what the linked page looked like. If you hit one of those nasty "Page not Found" errors, right-click and select the "Get near current time" option to see what the page looked like before it vanished from the web. When on a past version of a page - the Memento extension icon is now red - right-click the page and select the "Get current time" option to see what it looks like now.

Memento for Chrome obtains prior versions of pages from web archives around the world, including the massive web-wide Internet Archive, national archives such as the British Library and UK National Archives web archives, and on-demand web archives such as It also allows time travel in all language versions of Wikipedia. There's two things Memento for Chrome can not do for you: obtain a prior version of a page when none have been archived and time travel into the future. Our sincere apologies for that.

Technically, the Memento for Chrome extension is a client-side implementation of the Memento protocol that extends HTTP with content negotiation in the date time dimension. Many web archives have implemented server-side support for the Memento protocol, and, in essence, every content management system that supports time-based versioning can implement it. Technical details are in the Memento Internet Draft at General information about the protocol, including a quick introduction, is available at

For queries about the Memento for Chrome extension and the Memento protocol, get in touch at

The Memento team is also developing a plugin for Mediawiki that speaks the Memento protocol. The effort to get it into the English Wikipedia has stalled at the moment, but I expect the developers will give it another go at some point. Congratulations to Herbert Van de Sompel, Michael Nelson, Rob Sanderson and the rest of the team at Los Alamos National Lab and Old Dominion University.