Form events and event handlers
Much of the work and activity in a Mongoose-based application is accomplished with the
use of what are known as form events and form event handlers.
Loosely defined, "form events" are things that happen within the scope of individual or multiple forms. "Form event handlers", then, are directives that are provided to instruct the application what to do when a form event is generated or triggered.
Note: Mongoose-based applications also have other types of events and
handlers known as application events and application event handlers. In contrast to form
events and handlers, application events and handlers can be used anywhere in the application,
and are not restricted to individual forms.