5. Automatically Generated Links
It’s sounds like a sweet deal when someone offers to build bulks of links over night on certain targeted keywords. In any case, those people are using automated programs that post links in the form of comments, forum posts, wiki posts and so on. This is one of the most harmful link building techniques, it terms of “internet pollution” as it adds literally no value to the users and it is very annoying for everyone.
6. Widget Links
A form of link building technique that uses “WordPress like” plugins. The person that created the plugin has the possibility to inject links on all the sites that have that respective plugin installed. If the plugin adds real value to the user, and if the webmasters have the choice to link or not back to the website, Google might consider them natural.
Advertorials are articles that are published by sites as a form of advertisement. Google may consider this as a form of paid link tactic IF the links that point back to your site are not tagged as nofollow.
8. Text Advertisements that pass PageRank
Same story as in the case of advertorials. They may be considered as unnatural when they are left as do-follow and they directly influence the site’s ranking in the search engine.
9. Articles & Commercial Anchor Text
It’s a good thing that people write about your product or service and link back to your website. As long as a person creates links in a natural way, using brand keywords or navigational phrasing like “click here” or “visit this”, you won’t have any problem. You’re gonna feel Google’s wrath if they catch you stacking links with commercial keywords.
10. Web-Directory Links
It’s been around for a while now and it seems like it isn’t an absoleet link building tactic yet. People used to abuse these type of sites by placing links on hundreds of web directories. If your site’s link portfolio has mostly these kind of links you might get the unwanted attention of the Webspam Team. There are still high quality web directories on the internet where you can post your links, like Dmoz and Best of the web, that filter the submitted entries manually.
11. Footer links
A tactic popularized by web design agencies & used by them to increases their site’s visibility in the search engines, was to put links in the footer of their client’s pages with the wording such as “Designed by” or even commercial keywords such as “Web Design Agency Melbourne”. When you have a couple of those type of links and you don’t use commercial anchor texts you won’t have any problems. They will surely be categorized as unnatural if you’re using this linking tactic in excess.
12. Sitewide links
When you create sitewide links GoogleBot is going to see the link on almost every page of the website. One or two site-wide links won’t raise any suspicion but if you’re going to abuse this feature, most likely Google will place it under the unnatural links category. This type of link building is not recommended for new sites; it may be seen as a way to rank quickly … but it really isn’t.
13. Blogroll links
A technique that’s been around and abused just as long as the one with the web-directory links. There’s nothing harmful if you have 1-2 links and they are placed on relevant blogs. When it represents a huge chunk from the backlink profile it becomes clear to Google that those links are unnatural.