Distinct molecules called agglutinogens (a type of antigen) are attached to the surface of red blood cells. There are two different types of agglutinogens, type A and type B. Each type has different properties.
MDB: Geodatabase. The geodatabase is a collection of geographic datasets of various types, with the most basic types being vector, raster, and tabular data. There are three types of geodatabases: file, personal, and ArcSDE. Geodatabases are the native data format for ESRI's ArcGIS.
What are spatial types? Spatial types are data types that store geometry data. All the spatial information is stored in the spatial column; there are no side feature tables. Having the spatial information in one field makes it easier to access the spatial data outside of ArcGIS.