Back-links are simply the online markers aiming to your site. These indicators are textual content or images that are embedded with program code to point to your web page as indicated by the blue anchor text you see all over the place on the Internet. This website about link building explains various permutations of back links.
Back-link Creation that Works Well
Here is the first of three posts explaining the back-linking techniques which will get your web site on the top page of Google for a medium competition key phrase. You may use the Google keyword tool to view whether the key phrase ranks low, medium or high.