On-Site Optimization is not enough these days to get on the top of the search engines. For a proper SEO campaign you need offsite search engine optimization which should be 65% to 75% of your optimization efforts. Off site optimization consists of all the techniques not performed directly on your website which mainly are back links from other sites.

There are three different types of backlinks:

1. Reciprocal: When you have a link to a site that is linking to you. It is the easiest way to get back links since both you and the other webmasters are increasing backlinks but has less importance than one way links. Do not overdo reciprocal links or you might be banned from the major search engines.
2. Three Ways: It is technique created by webmasters to trick search engines into thinking the links are one way and not reciprocal. 3 ways linking is when you link your site to site b and site b owner links back to you from site c. This links have more weight than reciprocal links since you are tricking search engines into believing that the link is one way only. Always keep in mind that search engines don't like to be tricked and in the long run might penalize you.
3. One Way: Definitely the type of back link with the most value to search engines and the type that will increase your rankings the most. There are many ways to receive one way links the most important factor is to keep the source relevant to your subject.

Links Trading:

The oldest technique to link building. Link trading is also know as reciprocal links, links exchange and 3 way linking. Make sure you always trade links with relevant sources to your market for better search engine recognition. We recommend you use websites that specialize in this service such as linkmarket.net.

Article Distribution:

Really effective way to build one way back links. There are thousands of article distribution websites that allow to include a personal link at the bottom of the article. Always make sure you write your own quality articles related to your subject or in you might be banned. A well written article might also be used by other webmasters on their website if it is unique and properly written.

PR News Wire:

Through the years we have found news wire to be extremely effective to build one way links and search engines recognition. PR News Wires are expensive because are distributed to thousands of news sites and news channels. If you manage to write a good PR News Wire your story might be featured in newspapers to automatically boost immensely your link building campaign.

Directory Submission:

This is a time consuming but definitely worth job if you submit your website to relevant directories. Many important directories require a payment or a long scrutiny by the category administrator. Some directories as DMOZ, BOTW, Joeant.com and yahoo can make a huge difference in your rankings.

Bookmarking:

A great source of one way backlinks. Major bookmarking website don’t only provide a link to you but can also generate thousands of visitors.

Forums:

Forums signature links still have some value to search engines. Always try to post in relevant threads with relevant content. If you start writing fake threads just to promote your service you might be penalized and reported as a spammer.

Write Reviews:

Hundreds of websites and blogs review other sites, you can write your own review or request these websites to look at your product/service and post their opinion.

Blog Comments:

Do not spam blogs with irrelevant comments. If you are well educated on the subject share your views and comments on the post. If comments are relevant, constructive and subject related the webmaster will accept your comment and leave a link back to your website.

Buy Links:

This is a delicate technique since Google decided to remove from their index sites that were buying and selling links. If you decide to start using this technique do it in relevant websites and always try to make it look as natural as possible. Some pay per click engines show your posts as a valid backlink. Do not overdo this or you might be penalized.