Plus the site outside the chain will automatically add your page in front of the URL

Adding a link in the normal operation, substantially on the line with the href attribute. But when the place we want to jump on the discovery will add their own web pages in front of our web site.
This is because the page within it as a chain. Only preceded by http or https on it.
Because do outside the chain without http: //, then this outside the chain is invalid.
Plus it can have the effect of weight transfer.