Backlinking Observations 

Backlinking by definition; Also referred to as Inbound Links. Links from another website to your website.

Backlinking Usage

Encouraging websites to link to your site maintains and builds your sites ranking and is a great way to submit a website to the search engines. Google's Sandbox delay can even be minimized, to a degree, by using backlinking properly. As such, backlinking is a powerfully incredible tool for any Search Engine Optimization campaign.

It has come to the attention of some that when viewing their website server logs other sites have linked to theirs, which would normally be something to be happy about. The web was designed to share information, linking sites together so when information on one website is updated everyone linking to that source stays current. The search engines recognize this. When your site is linked to by others this then shows the search engines and the rest of the world that your website is worthy of quoting. You want people linking to your website... usually...

Backlinking Usage... that can be bad

It should be noted that the content on your website is yours. The linking on your website is of your creation. If you link to a website nobody should have coerced the creation of that link. You add that link so that others can benefit from the content on that site. You have little control, and typically NO control, over what others place on their website. If you do not like a website linking to yours you are probably powerless to do anything about it.

This issue that has been created is from the discovery of the search engines' valuing of these links and thus people trying to manipulate these search engines' rankings of their site by building artificial linking. Of course the search engines then fight back by devaluing some websites, or groups of websites such as linking farms. For a while, Google was even devaluing the sites linked to by devalued sites; ouch!!

Conclusion

As stated above, you have little to no control over who links to you. The trick is to fill your website with incredible content convincing the world that you are an authority on a subject and worthy of being quoted. If weird sites are linking to you then build your content encouraging linking from a greater number of legitimate websites or those that you are not embarrassed of. An online presence can be a scary experience, but when handled knowledgeably the positive aspects will outweigh the oddities.