Links are one of the most important signals in Google’s ranking algorithm. Most people know that links from external pages are important. However, the internal links on your website also contribute to your rankings:
Google gives more value to pages with many links. Links from external websites help Google to see the overall value of a web page in comparison to other pages on the web. Internal links help Google to see the importance of a web page in comparison to the other pages of your website.
Pages with many links are crawled more often by Google. If you want to show Google that a particular page is important, make sure that you link to that page from many other pages of your website.