Feature layers and table views serve as intermediate datasets held in memory for use specifically with tools such as Select by Location and Select Attributes. Although these temporary datasets can be saved, they are not needed in most cases.
Feature classes are physical representations of geographic data and are stored as files (shapefiles, personal geodatabases, and file geodatabases) or within a geodatabase. ESRI defines a feature class as "a collection of features that shares a common geometry (point, line, or polygon), attribute table, and spatial reference."
Feature classes can contain default and user-defined fields. Default fields include the
OBJECTID fields. These fields are ...