Autodesk Inventor Content Center libraries provide standard parts (fasteners, steel shapes, shaft parts) and features to insert in assemblies.
Two types of parts are included in the Content Center library: standard parts and custom parts. Standard parts (fasteners, shaft parts) have all part parameters defined as exact values in the table of parameters. Custom parts (steel shapes, rivets) have a parameter set arbitrarily within the defined range of values.
The basic component in a Content Center library is a family (part family or feature family). A family contains family members that have the same template and family properties, and represent size variations of a part or feature.
Families are arranged in categories and subcategories. A category is a logical grouping of part types. For example, studs and hex head bolts are functionally related and are nested under the Bolts category. A category can contain subcategories and families.