Metadata

Definition: Information that describes data. 

Explanation: In order for data to be useful they must be seen in context.  A document having two columns listing dates and stream temperature is useless unless you know the information that goes with it such as what stream this is and how were these measurements taken.  There are other useful pieces of information too.  Some examples are: Ownership, time coverage, spatial coverage, sampling and analysis methods, citation information, contact information, and distribution instructions.  Metadata makes it possible to discover and share data. 

Example: Consider the image on a photograph to be the data.  Then, information such as where the picture was taken, when the picture was taken, what kind of lighting was used, and what kind of camera was used would be metadata.

Now consider a large collection of literature and data with a search engine.  Let’s say that search engine knows, for example, that the Central Arizona - Phoenix Long Term Ecological Research Site is characterized as an urban research study.  Now it is possible for that search engine, when asked about urban ecology, to pull up data from the Central Arizona - Phoenix collection even if the data are not directly about urban ecology.

Why it is important: There is no way to combine data without metadata.  Things you might take for granted today, such as a web search engine, cannot exist without metadata.

Contributed by BES Information Manager Jonathan Walsh