Using Disqus for Blog Comments
Disqus is a commenting system that allows users to leave comments on blog posts made with the Built-In Blog.
You will need a Disqus account to use the commenting system, click to Sign up for a Disqus shortname. Click on I want to install Disqus on my site to set up the Disqus Shortname.
Once you have a Disqus account, you can use it for blog comments by turning on the Disqus Comments switch and entering a Disqus Shortname.