What’s a mash-up?

I’ve done a post for the Reputation Online site, produced by the good folks at Centaur/New Media Age explaining what mash-ups are:

In the last few years, the term “mash-up” has been increasingly used to describe online sites and services, but it is only rarely explained.

The basic concept is that a “mash-up” is a combination of services or data from two or more different sources into one new, combined output. For example, you might take traffic accident data from one place, a mapping service from another place and mash them together to produce a map with pins on it indicating where traffic accidents occur.

Combining information together is nothing new (after all, what is writing a non-fiction book other than taking ideas and information from different places and combining it in one publication?).

What makes mash ups distinctive is their dynamic nature and the changes in attitude towards information that they trigger.

The dynamic aspect is important because by combining data from feeds that get updated (such as RSS), rather than just taking a static snapshot of information, the resulting mash-up itself gets updated as and when the source data changes. Where the source data changes regularly, such as with a weather forecast or sports results, this means the mash-up too changes, rather than being a one-off combination.

Successful mash-ups take data and reuse it in interesting ways that get more out of it, and get it to a wider audience, than the original source. But in order to do so, the provider of the data has to be both willing to let their data be used in this way – and to provide it in a way that allows for easy mashing up. RSS feeds, APIs and XML formats are in; pdf files uploaded to an ftp site once a year are out.

Hence the changing attitudes towards information that mashing up can trigger. Traditionally people have often been very protective about their own data; in the world of mash-ups you want others to take, manipulate and pass on your data. That is not always a comfortable experience for people used to more traditional attitudes. But for some great examples of the benefits that mash-ups can bring, see the award winners at http://mashupawards.com/winners/

A footnote: “mash-up” is also used in several other areas, such as to describe a song which is made up of parts of existing songs, mixed together to produce a new song, or a video clip that mixes together sound and pictures from different places.