Is nofollow a good thing?

What is nofollow?  It is an HTML attribute value for ordering search engines that a hyperlink should not influence the link target’s ranking in the search engine’s index.   The purpose of having this is to reduce the possibilities of  search engine spam, thereby improving the quality of search engine results and preventing spamdexing from occurring.   It means that if you add the nofollow value to your link, the link juice will not be shared the corresponding landing page.    nofollow tags are also used by most bloggers who wanted to avoid spammers who used to comment in order to gain backlinks from the comment sections of blogs.  nofollow is also loved by webmasters because it could avoid page rank passing also called as PR leakage.  Contact pages, about corporate pages and review pages should be ‘nofollowed’ since it should give all page rank to main product pages or main catagories.