For example, you may have a feature source that contains data for roads. Feature sources can be stored in the library repository or in a session repository. A feature source identifier describes a complete path in the repository. For example,
Within a single feature source there may be one or more feature classes. A feature class describes a subset of the features in the feature source. In many cases, there is one feature class for each feature source. For example, there may be a Roads feature class in the RoadCenterLines feature source.
A feature class contains one or more features. Each feature has a geometry that defines the spatial representation of the feature. Features will also generally have one or more properties that provide additional information. For example, a feature class containing road data may have properties for the road name and the number of lanes. Feature properties can be of different types, like strings, integers, and floating point numbers. Possible types are defined in the class MgPropertyType.