Custom objects can be assigned categories, lifecycle states, and properties.
Categories
Categories can be assigned to custom objects in two ways: when the custom object is created and when the user performs a change category event on the custom object. By assigning custom object instances to a category, properties and lifecycle definitions associated with the category are automatically applied to the instance.
See Work with User-Defined Properties for more information.
Lifecycles
Just like files and folders, when a custom object is assigned a category, it automatically inherits the associated lifecycle definition. Lifecycles can be configured to automate certain behaviors based on the custom object's status in the lifecycle. Lifecycle settings are configured by the administrator.
See Lifecycles Administration for more information.
Properties
Categories can also be used to assign user-defined properties to Custom Objects. There are also out-of-the-box properties specific to custom objects, such as Custom Object Name and Custom Object System Name.
See Work with User-Defined Properties for more information.