By default, when a Form is created, Zoho Creator will have a table generated at the back-end to store data submitted through the Form. These Forms are called Regular/Normal Forms. For example, when you create a Sales Form, a table named Sales is created and all data submitted through the Sales Form will be stored in this table. The Sales Report will display the data stored in the Sales Form/table.
Screen-shot of the Sales Form
Screen-shot of the Sales Report that display data submitted through the Sales Form
When you add a new form to your application, Zoho Creator displays the check-box option "Data will be stored in creator", which is checked by default. De-selecting this option will create the Form as a Stateless Form with scriptable buttons that does not generate a table at the back-end. (i.e) when you click on the Form button, the entered data is not automatically added to the table as an inserted record. Instead, you can add custom buttons and execute actions in the "on click" event of the form. The scripts act on the "on click" button and can be programmed to do anything you can do in Deluge Script.
For example, in the screen-shot given below, the Form named Enter Month/Year is a Stateless Form which enables a user to select the month/year and generates a report on click of the Generate Report button.
Refer the topic, Creating Stateless Forms for more information.
A subform is a form within a form. The primary form is called the main form, and the form that is inserted in the main form is called the subform. Subforms are generally used to show data from tables that have a one-to-many relationship.
Refer the topic, Creating SubForms for more information.