Validating web pages
Note: if you are not sure what HTML and CSS mean, please read What are HTML, CSS, Java Script, PHP and Perl? For those unfamiliar with the term, "validating" a page is just a jargon-filled way of referring to the use of a computer program to check that a web page is free of errors.
Important Validating user input is also important for security.Therefore, you also have to make sure that the values that users enter can be correctly converted to the appropriate data types.You might also have certain restrictions on the values.This article discusses how to validate information you get from users — that is, to make sure that users enter valid information in HTML forms in an ASP. What you'll learn: If you ask users to enter information in a page — for example, into a form — it's important to make sure that the values that they enter are valid.For example, you don't want to process a form that's missing critical information.