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user. This methodology allows a complete understanding of the content of each simple 
object. 
Building a Data Product 
The following diagram is an example of what a simple data product might look like. In this 
case, the product contains information on the production of the product and an object of 
identification information containing catalog data pertaining to the product (e.g. platform 
ID, data type, time span). Following this are two Description Data Units (DDU), one for 
the application data object and the other for the supplementary data object. Finally, there 
are the instance data comprising an supplementary (or ancillary) data instance and the 
instance of the application data itself (e.g. the image). 
PHYSICAL PRODUCT INFORMATION 
IDENTIFICATION INFORMATION 
DDR FOR SUPPLEMENTARY DATA 
DDR FOR APPLICATION DATA 
SUPPLEMENTARY DATA INSTANCE 
APPLICATION DATA INSTANCE 
The exact content and order of the content of a product varies with the problem at hand. 
The amounts and types of metadata and supplementary data may be more or less than that 
shown. In other words, all of the information needed to understand and analyze some 
collection of data should be packaged with it in some manner. 
Most data products contain multiple instances of data and metadata. Each instance is a 
group within the product containing, for example, an application data instance (e.g. an 
image), a supplementary data instance (e.g. calibration data), and the identification of the 
unit (e.g. time and location of the data). An example of such an instance is shown below. 
This unit is termed an information unit. 
IDENTIFICATION INFORMATION 
SUPPLEMENTARY DATA INSTANCE 
APPLICATION DATA INSTANCE 
In this case, the overhead may be lessened by not repeating the data description with every 
instance. Hence the product diagram looks like the following (& indicates that this unit may 
be repeated many times):