Google discovered “nofollow†with the purpose of supporting web-masters and site owners counteract spam. All this was established in 2005. With blogs as example wordpress inbuilt comments are nofollow, but are possible to set as dofollow if required by you, which is a benefit for users who have knowledge with this to comment in a particular site.
I learned to ride a bike when I was four. I learned to tie my shoes before then. I like jelly donuts.