Google gives a PageRank to every web page and this pagerank signifies the credibility and worth which Google gives to the particular web page. PageRank is one of the algorithms of Google and it is named after Larry Page, the inventor of the formula. The pagerank can be from 0-10 and web pages which are not considered to be worthy at all in the eyes of Google are given the pagerank of N/A.
There are many factors depending upon which a web page can receive a high pagerank from Google. Firstly, the information provided on the web page should be creditable and worthy. The content on the web page should be original, innovative and informative. Moreover, the number of external links on the web page also plays a vital role in this regard. A web page which has too many irrelevant outbound links would not be able to impress Google and would not receive a higher PR. It should also be noted that pagerank is for every single web page, and not a website. A website which has many pages would have different pageranks for every other web page.
The Google PageRank or PR has great significance in search engine optimization. Search engine optimization is the collection of all the procedures and techniques by which a website can be driven to higher rankings in the search engine result pages of all the major search engines. Search engine optimization involves the organic or free results only. By effective search engine optimization processes, the ranking of a website in the results of search engines for the targeted keywords could be improved. The major search engines are Google, Yahoo!, Bing and Baidu.
Google PageRank or PR is very important for search engine optimization because a web page which has a high pagerank has higher chances of appearing in better rankings in search engine result pages. Moreover, backlinks for a website on web pages which have a higher pagerank are extremely valuable as well.
Every search engine has its own undisclosed algorithms. Usually, search engines, particularly Google, assume a backlink to be a vote in favor for the website. The quality of the backlink is of importance as well. The higher number of high quality backlinks of a website, the higher rankings it is supposed to capture. A backlink on the web page which has a high PR is a high quality backlink. Other factors which are important to make a backlink of high quality are relevancy and the number of outbound links on the web page where the link is placed.
It is also mentioned by experts that when a web page has backlinks of pages which have a high PR, then the pagerank of the particular web page for which the backlinks are created rises as well.
If you have a website, then you should ensure that every page of your website is considered to be worthy by Google, since Google is the most popular and widely-used search engine.