Instant field validation

1. What is field validation?
2. What are the different types of input validation?

What is field validation?

Field validation is an automated process of ascertaining that each field contains the correct value before the form is accepted. The concept is straightforward. Does the phone number field contain a phone number?

What are the different types of input validation?

There are two different types of input validation approaches: whitelist validation (sometimes referred to as inclusion or positive validation) and blacklist validation (sometimes known as exclusion or negative validation).