Link Juice is very important aspect taken into consideration by Google for ranking a website. More inbound links a site has, more it receives link juice. Strong inbound links help a website in getting on the top of a Search Engine Result Page. Only quality inbound links help in creating good quality link juice that is beneficial for your site and help in achieving high Page Rank.
Juice is the term used for how much benefit a link passes on, as not all links are equal.
A link is assumed to pass more link juice if
1. it does not have the no-follow attribute added
2. the page the link is on is indexed by the search engines
3. the number of links on the page that the link is on are low
4. a page with a higher mozRank and mozTrust is likly to pass more link juice
Link juice is the key factor in link building. If we build link from a high PR site, then we will get all the benefits of that site. But those link should be do follow. By no follow links we can promote our site but will not have any juice from that site.