There are millions of sites in the Google search engines.We are accessing so much of sites without knowing basic info about them. To know the basic info about a site type “info:” and without adding a space type the domain. Eg: info:shipmethis.com. Now we know how to know basic info about a site.
How to know back links linked to your site. For that just like above, type “link: your domain” in Google search. Do not forget to add space after “link: “. Eg: link: shipmethis.com.
To Check XML Validation
Go to XML validator by W3 Schools. It is an easier way to find the missing codes or other possible errors.
What if you want to check the errors for your own blog?
General conformance check : It performs as many checks as possible for a site or blog.
CSS profile validation : Checks the validity of against CSS 1, CSS 2, CSS 2.1 and CSS 3 profiles
Mobile OK checker : Checks whether your blog is good for mobiles
You do not have to use custom task because you will not enough time to correct errors got from above checks..lol.. Go to the site and enter your site like http://www.shipmethis.com. Then you know what to do. Check each item for errors and only correct errors you know, unless skip it. You don’t have to correct all errors because you can’t. Just read it all and try to identify which error makes your site load slow or make visitors say: Alas!! Its gone..
You can use http://validator.w3.org/i18n-checker/ to check Doc type, language and all. This is a good and most important way to do it. This is the base of your html. All configurations starts here. So try to avoid errors.
How to know what prevents your site from a good mobile version?
Use this and you will not use any other such checkers..
This mobile version checker list the size of the web page. It lists all the sizes of the scripts, CSS files and images. The tool gives you the exact info you need to optimize your HTML template and make it cleaner.