Where is validation attributes?

Question

teh validation attribites are: pattern, requiered and novalidate and others for form tag

Answer 1

Although I didn't heard about any attributes named validation attributes.
Validation is a process to validate the data that the user/viewer of your web page provides. For an example, let's say in your web page there is a contact form or sign up form, what will happen if user provide 648292638(any number) as his name and 64838ash7g2822(anything without @) as his email ID. We know this is not a valid data, so if you do not use any validation techniques then these invalid data will be written to your database, and definitely you don't want it to happen. HTML language has many valid techniques [in a form, the type attribute of input tag is also for validation]. But HTML's validation techniques may fails to properly validate your user data. JavaScript has the better capabilities to validate form data.

The above contents is about validation of form data. There is also an another meaning of validation. It's the following contents.

You may not be sure after writing the whole codes I mean tags and their attributes of your html page is property written or not. To check this you need to validate your documents. This is also mean validation. You can do this in W3C's official website.
I hope you got your answer.