What are validations?

[sonia sharma]

HTML form validation can be done by a JavaScript.
Data validation is the process of ensuring that computer input is clean, correct, and useful.
Typical validation tasks are:
1.has the user filled in all required fields?
2.has the user entered a valid date?
3.has the user entered text in a numeric field?

[Guest]

Validation is defined as the collection and evaluation of data, from the process design stage throughout production, which establishes scientific evidence that a process is capable of consistently delivering quality products. Four types of validation are:
A) Prospective validation
B) Retrospective validation
C) Concurrent validation
D) Revalidation