Knowing these schemes can help you to save your resources and keep from being penalized by Google. These schemes for those who have negotiated with and are planning to get backlinks from other sites for some consideration.

Backlinks Must Be in Form of Natural Links
Based on SEO experts, Google gives more weight to backlinks from natural links. Natural links means that links to your site must be provided by the other sites or blogs voluntarily. These links to your site must not be solicited, paid and/or begged from other sites. Otherwise, you’re just wasting your time, effort and money. Worst, your site could be penalized for these unwanted schemes.

Backlinks Schemes That Must Be Minimized or Avoided
Below are the 12 backlinks schemes or strategies that must be minimized or avoided. These backlink schemes, however, have no effect to sites or blogs that are being linked to voluntarily as these are beyond the control of its owners.

1. Backlinks from sites with links to bad neighborhood. Links from other sites or blogs that also link to hacking, spamming, porn, gambling, link farms and other bad neighborhood sites have no effect in your site’s PageRank.
2. Backlinks captioned as sponsored, paid, ad and the like. If you have paid for this backlink scheme, you’re just wasting your money or your resources. These backlinks have no effect in your PageRank as these are considered by Google as just an ads. As per the Quality guidelines - basic principles of Google’s Webmaster’s Guidelines, webmasters are warned not to participate in any link schemes designed to increase site’s ranking or PageRank. Read this very useful beginners’ guide on buying links for SEO.
3. Backlinks from sites not indexed by Google. If you search the site with Google and shows no results. That means the site is not indexed.To query if site is indexed, type the site URL in Google search box without “http://” , then click Search. Alternatively, copy and paste this: http://www.google.com/search?q=www.transdisplay.com and replace with other’s site domain and press Enter. This is also an indication that the site may have been penalized by Google, if the site is more than one year old.
4. Backlinks from sites with 100 links or more. It is also stated in the Design and Content Guidelines of Google’s Webmaster Guidelines to keep the links on a given page to less than 100. Otherwise, the page will not be crawled. So, links on this page will not be counted for PageRank.
5. Backlinks from sites or pages with PR0. If the site or page is more than 1 year old and still has zero PR, it is an indication that it is being penalized by Google. Some sites and SEO experts, however, disputed that delayed indexing and ranking of good websites could be the effect of Google’s sandbox.The Sandbox Effect is the theory that websites with newly-registered domains or domains with frequent ownership or nameserver changes are placed in a sandbox (holding area) in the indexes of Google until such time is deemed appropriate before a ranking can commence. See more discussions and disputes onSandbox at Wikepedia.
6. Sudden increase of backlinks. Abrupt increase in the no. of backlinks to your site especially from non-popular and non-authority sites could be seen by Google as padding or spamming. Normally, natural backlinks increases abruptly if the site or blog has been cited by the authority and/or very popular sites that make a big buzz on the net.
7. Backlinks from websites or blogs with the same IP C Class. Sites having the same first 3 parts of the IP addresses are in the same IP C class. These sites are being treated by Google as related to each other. Hence, backlinks from sites with the same IP C class are given less weight for PageRank. For example, sites A, B and C that are linking to your site have the same IP addresses of 123.456.789.xxx in
   the first 3 parts except for the last part xxx.Here is a very useful Free IP C Class Backlink Analyzer Tool that investigates the backlinks pointing to a website and groups them according to the C-Class IP addresses they come from.
8. Backlinks from sites with irrelevant content. Having backlinks from other sites’ pages with irrelevant content have less effect to your site or blog. For example, the site linking to you is about “hollywood celebrities” while your site is about “work at home”.
9. Link Titles of backlinks are the same. Backlinks with the same link title from other sites are ineffective to increase PageRank. For example, sites A, B and C are linking to you using the same text link of Work At Home like this Work At Home. To be effective, Site A, B and C must be linking to your site using different your site’s top keywords like “Work At Home”, “Make Money Online” and “Make Money At Home” as link titles.
10. Temporary backlinks or links for a short period of time. Links to your site must be permanent to be counted as legitimate backlinks to increase PageRank. Backlinks must stay for a minimum of 3 consecutive months to be considered for pageranking.
11. Backlinks from Press release sites. Links to your site from popular Press Release sites like PRWEB have no effect in PageRank. But, backlinks from other sites as a result of your press release are considered as natural backlinks.
12. URL format of backlinks are inconsistent. You may notice that my site’s URL http://www.transdisplay.com and http://www.transdisplay.com/index.php have different PageRank though they both refer to the index page. For consistency, always use the format: http://www.your-domain-name without index.php or index.html.

Learning these schemes that must be minimized and avoided can really help you save much of your time and other resources, including money. In my opinion, the best strategies to have an effective backlinks for the purpose of increasing PageRank of your site or blog and its pages, are to comply with Google’s webmaster guidelines on the design, content, technical and quality and to submit your pages to popular communities, directories and networks to attract natural 1-way links from authority and popular sites. (freetipsw)