It is well known that it is not sufficient for a good ranking to only have an optimized website for the keywords. More important are links from other sites to your website. It is for sure not bad to know something about the different kinds of Links.
You can exchange links with another site. Therefore you contact the webmaster and offer him a link. You get a backlink pointing from his website to your website if he agrees. Those links are reciprocal links or Two Way Links. Keep in mind to ask for a link from related sites, they are more important to Google. Look for links from your competitors, they are most related. But you would rather sell your own product and do not want to advise the product of your competitors. more..increase your pagerank
Two Way Links don’t increase your ranking significantly in Google, certainly they are better than no links. Google loves One Way Links. Thats a link pointing from the other site to your website, and you don’t link back to the other website. You can get such links from web directories. But they contribute less and less to a good ranking. One Way Links would be of course again the best of a competing site because they are very related. You sure have problems to find somebody who gives you a link for nothing in return.
However if you have two partners B and C, you can proceed in a different way. You (A) link to B and B doesn’t link back to you (that would be reciprocal) he links to C. C then links to A. Everybody gets an incoming link, but for which there is no direct outgoing link. All are linked in a triangle: A -> B -> C -> A. Search engines evaluate each incoming link as a one-way link. This is the best for your ranking. more..Getting Backlinks with LinkNetworks
If you have many domains you can reach better ranking with clever linking. What do you do, if you have only one ore a few websites. The answer for this are Link Networks. These are networks of several thousands of websites of their members. For a low monthly fee, the three- or polygonal linking takes place over the network. more..getting many backlinks