Applications often have features in common. For example, you might often reuse features like the following:
A processing package that calculates commissions or performs statistical analysis
A Close button that performs a certain set of operations and then closes the window
DataWindow controls that perform standard error checking
A list that includes all departments
A predefined file viewer that you plug into a window
If you find yourself using the same application feature repeatedly, you should define a user object: you define the user object once in the User Object painter and use it as many times as you need.
There are two main types of user objects: class and visual. Class user objects are also called nonvisual objects.
