Multi Line Text field allows you to create fields where you can insert large text. It is appropriate for description fields, etc.
Create Field and Set Its Attributes
You can set specific attributes when you are creating the field (values in the picture are only examples):
|Mandatory field that sets also the title of the field that will be displayed in the dialog.
|Optional description of the field.
|Set the height of the field that will be displayed without scrollbar.
|Set the category of fields.
|You can mark that you want to display the custom field also in the General section, not only in the Custom Fields section.