Metadata is data about data.
Metadata is a set of data that has meaning.
Metadata is a set of data that can communicate to user for a particular purpose.
Metadata is a map that give you a special view of reality.
When we do cataloguing, we are creating metadata of the book/resource in hand. We describe the set of attributes that we think they are needed by users in order to find, identify, select and obtain the information. This is the particular purpose that we want to communicate with the users. We follow the metadata schema, AACR or RDA to describe the meanings. We follow standardised vocabularies when describing some attributes (e.g. subjects, authors).
Different people have different ‘taste’ of metadata to the same things. For example, to scrap collectors, the metadata of books required may be weights (in terms of kilograms), types of paper, etc. So different metadata sets reflects different views of books. Karen Kcoyle used the analogy of maps to describe metadata:
“[a] subway map often is not accurate in terms of scale and distances. But that’s not its purpose. Its purpose is to help you navigate a complex subway system, to make your transfers at the right places, and to get to your destination. This map is designed for that purpose.”
The analogy of map help us to think that the metadata of a book is not alone, the data is part of the map. It connects with other metadata helping users to navigate, transfer, and find the right things. A catalogue record is not alone. Our work is not to create a metadata record for a book but to create connection of the new item in the bibliographic universe.