Are back link can increase Page Rank?

Are back link can increase Page Rank?
If you want have a good page rank, you must have much backlink with website or another blog. Are backlink can increase Page Rank? “Yes”. But, are backlink is a prime matter? The answer is not 100% we are page rank can increase only with use a backlink. Until now google still looking how many important we are website or blog in another person blog. 
Except use a backlink we must do this step: 
1. Update artikel every 3 day (minimal)
2. Give a content like a free software or free e-book
3. Give a Video Clip content 
4. Give a Newsletter content 
5. Use a feed reader from another blog
So, we can say if back link not only one way to increase page rank.