The measure a value that’s pass through website to website using links for visualization purposes we think each website has having a piggy bank full of link equity that it can pay to other sites.
Link equity can work on a macro scale between sites and also on a micro scale with in pages of your own website. So you have your home page and of course if you have sitemap and robots.txt better they help the search engine to find the way around your site. But you also probably link to some other pages in your website from your home page. These are called internal links.
Here is the example of website with some internal links on it. On moz.com home page, you can see some internal links that you can click on to get a product pages. Each of these internal links passes an equal amount of link equity to the page it links to.
So when Google crawl this website, it is going to pay equal amount of attention to each one of these internal links and it should crawl all three of them with the same frequency. Assuming there is nothing in the sitemap and robots.txt file otherwise Google will recognize the same relationship between the Moz home page and each of these internal pages.
External links between pages pass on link equity too. Google uses the link equity to decide how that page should be ranked in the search results. The more pages that link to the moz website, the more votes they get. Also it will accumulate higher quality pages link juice.
So you can see why earning link equity in specifically earning high quality of links from high quality website is such an important part of SEO strategy.