Each field in the form can have zero one or more validations. More info & downloads where Do My Validation One() and Do My Validation Two() are custom functions for validation.
For example, you can have an input field that should not be empty, should be less than 25 chars and should be alpha-numeric. In some dynamically programmed pages, it may be required to change the validations in the form at run time.
The purpose of a form validation script is to return a boolean value ('s to reference form fields, but that can lead to namespace conflicts and why make things more complicated than necessary.