Roxana - Gabriela HORINCAR Refresh Strategies and Online ... - LIP6

Introduction
In the last twenty years, the Internet has greatly evolved from a hypertext publishing
system to a platform of participation and collaboration [O’R05] among users, also referred
to as Web 2.0. The Web 2.0 services make it easy for individuals, companies and even
non-technical amateurs to create and manage their content online. In particular, many
Web 2.0 applications have emerged that allow users to manage, collaborate and share
their personal information on the Web. Examples include social networking sites for
keeping in touch with friends, family and business partners, online galleries for photos and
videos or blogs for sharing diaries or travel journals, such as Blogger [bloa] blog publishing
service, Wikipedia [wika] online encyclopedia, Flickr [fli] photograph sharing, Delicious
[del] bookmark sharing, Digg [dig] social news website, Facebook [fac] social network and
Twitter [twi] microblogging service.
This great accessibility of the Web 2.0 applications empowers users in the creation and
management of content and has led to an explosion of new online materials, also known as
user generated content (UGC). In 2006 Time magazine featured UGC as the ”Person of
the Year” [tim], in which the person of the year was ”you”, meaning all of the individual
online content creators who contribute to user generated media. Other examples that
illustrate the general online dynamics and rapid growth include the collaborative online
encyclopedia Wikipedia [wika] that reports reaching almost 8000 updates per hour for the
English articles and 2000 for the French ones [wikb]. Analyzing blogosphere growth, NM
Incite [nmi] tracked over 181 million blogs around the world by the end of 2011, up from
36 million only five years earlier in 2006. The free news aggregator Google News [goob]
covers news content aggregated from more than 25,000 publishers [gooc] from around the
world and covers about 4500 sites for the English language, each of them having its own
independent publication activity. Furthermore, there are numerous services that offer real
time monitoring and live updates and analysis of the stock market, domain known for its
highly dynamic nature.
The rapid growth of online information sources makes it difficult for a user to stay up
to date with what is new on the Web. This problem has been partially solved by the
introduction of the RSS [rssa] and Atom [ato] data formats, that have become the de-facto
standards for efficient information dissemination. They allow the users to stay informed
by retrieving the latest content from the sites they are interested in. Technically speaking,
an RSS feed is a standard XML document containing a list of items, the publication of
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