Memento is a United States National Digital Information Infrastructure and Preservation Program (NDIIPP)–funded project aimed at making Web-archived content more readily discoverable and accessible to the public.
Technical description
Memento is defined in RFC 7089 as an implementation of the time dimension of content negotiation, as defined by Tim Berners Lee in 1996. HTTP accomplishes negotiation of content via headers. The table below shows the different headers available for HTTP that allow clients and servers to find the content that the user desires.
To understand Memento fully, one must realize that the header provided by HTTP does not necessarily reflect when a particular version of a web page came into existence. Also, the header may not exist in some cases. To provide more information, the header has been introduced to indicate when a specific representation of a web page was observed on the web.
Usage
One can find copies of page by simply navigating, in a web browser, to a link formatted, replacing urltoarchive with the full URL of the page desired:
JSON description of a Memento: http://timetravel.mementoweb.org/api/json/YYYY/urltoarchive http://timetravel.mementoweb.org/api/json/YYYYMM/urltoarchive http://timetravel.mementoweb.org/api/json/YYYYMMDD/urltoarchive http://timetravel.mementoweb.org/api/json/YYYYMMDDHH/urltoarchive http://timetravel.mementoweb.org/api/json/YYYYMMDDHHMM/urltoarchive or redirect to a Memento with a datetime that is close to a desired datetime: http://timetravel.mementoweb.org/memento/YYYY/urltoarchive http://timetravel.mementoweb.org/memento/YYYYMM/urltoarchive http://timetravel.mementoweb.org/memento/YYYYMMDD/urltoarchive http://timetravel.mementoweb.org/memento/YYYYMMDDHH/urltoarchive http://timetravel.mementoweb.org/memento/YYYYMMDDHHMM/urltoarchive
References
External links
Memento Project
The When of the Web - Extensive information about the proposal and experiment is available in the November 2009 paper Memento: Time Travel for the Web http://lanlsource.lanl.gov/hello http://www.cdlib.org/cdlinfo/2010/02/04/web-archive-discovery-memento-implementation-meeting/