what is clocking and how to check clocking ?

what is clocking and how to check clocking

You posted a question expecting someone going to explain everything ? Can you first try reading threads in this section ?

It's called cloaking. Search for it on this forum and you'll find tutorials.

Cloaking is presenting different content to Google bot and users.
To check if the site has cloaking you have to check it in the Google mobile test "Mobile-Friendly Test"

There is something called as Google in case if you don't know.

This technique is part of blackhat SEO. One should not use it. When user search for any site then web browser displays the information of correct website but when you actually visit that information that time it redirects you to different site.

It happens many time that we search for some different site and you are redirected to pornographic site, it is nothing but cloaking. Purpose of it is to increases the visitors for the site and site rank get increases.