| Spread for ASP.NET 9.0 Product Documentation > Developer's Guide > Understanding the Product > Concepts Overview > Underlying Models |
Spread for ASP.NET provides the following underlying models for each sheet and each set of headers in the spreadsheet:
| Sheet Model | Classes and Interface | Description |
|---|---|---|
| Axis model | Basis for how the sheet of cells is structured in terms of rows and columns. | |
| Data model | Basis for the manipulation of data in the cells in the sheet. | |
| Selection model | Basis for the behavior of and interaction of selected cells in the sheet. | |
| Span model | Basis for how cells in the sheet are spanned. | |
| Style model | Basis for the appearance of the cells in the sheet. |
Each model object is provided as a base model and a default model. The base model is the base on which the default model is created. The base model has the fewest built-in features, and the default model extends the base model.
The default models are provided as the models with which you will most likely want to work in Spread. They provide the default features that the Spread component offers.
However, if you want to provide different features, you might want to extend the base models yourself, creating new classes. One reason you might do this is if you want to create a "template" component for all the developers in your organization to use. By creating your own class based on one of the Spread base models, you could provide such a template.
The shortcut objects access the interfaces in the model namespace. When you work with shortcut objects, you are actually working with the interfaces of the models in the component. For example, if you change the background color of a cell using the Cells shortcut object, the interface for the sheet style model is updated with that information. For more information on the shortcut objects, refer to Shortcut Objects.
For more in-depth information on the models, refer to Using Sheet Models.