Page rank: Every site is given a page rank from zero to ten. The basic rule that can increase a page rank is to get links from other websites and limit the number of links going out to other sites.

Incoming links:
The quality of links is an important factor. Google looks for sites that have natural link popularity. It means that a variety if sites have to be linked and not just one type. Also link text is important. Relevance of the links is also important

Page titles:
This is one of the most important factors of the page that the algorithm looks at.

Keyword density:
If keywords are used too many times then it is a sign of spam to Google and will actually hurt the sites ranking. A good idea is to keep keywords density lower and instead use related keywords.

Age of domain:
The age of a domain can be a friend or enemy for SEO. Newer domains are difficult to be ranked but domains that are two years old are much easier.

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