Each project can contain many different components.
The different components a project can contain are
Adding new components creates a blank component in your project. You can add new modules, forms, and class modules to your project. You are responsible for updating all the properties of the component (such as the name of the component) and for filling in the appropriate code. When naming new components, remember that other developers may want to use your components in future applications. Follow the appropriate naming conventions for your development team.
The object component represents the type of object, or document, that the VBA code will access. For AutoCAD VBA projects, this object represents the current AutoCAD drawing.
The form component contains the custom dialog boxes you constructed for use with your project.
The code module component contains your generic procedures and functions. A standard module is also referred to as a code module, or as simply a module.
The class module component contains all your own objects, which are defined as classes.
The reference component contains all your references to other projects or libraries.