Search Engine Optimisation (SEO), like many things, will only work for you if you do it right. Employing dubious or outright illegal SEO tactics can land your website in a world of trouble, namely a Google penalty.
Keyword Stuffing
This is an amateur mistake many newcomers tend to make. You may have heard that keywords are the way to optimise your web pages so search engines can rank your website higher. However, keywords are not all there is to SEO. Think of keywords like sugar in tea—too much makes the sweetness unbearable, too little, unnoticeable. Inserting keywords into every single sentence on your web page will be enough to flag your whole site as spam, and you will suffer a Google penalty. It will be extremely difficult for you to come out of a bind like that without switching to a new domain name. Keep that in mind and use keywords very wisely and in moderation.
Keyword Dilution
This keyword related crime is similar to keyword stuffing, but it’s not exactly the same. Let’s start with an example. Say you are a company that sells oranges. You have a webpage optimised for the keyword “orange” and you receive a lot of traffic from search engines for that particular keyword. You notice this, and decide to use the fame of one keyword to sell other products, like orange paint, orange lipstick or orange hats. What happens now is that the meaning of the keyword applies to a long range of products, shifting the focus away from the original product. This is technically termed “keyword dilution” and is punishable with a penalty.
Plagiarism
Just like in school, publishing content belonging to other people as your own on your website is “illegal” when it comes to SEO. Your entire site could, and most likely will, get flagged. Remember that, if the original content creator finds out you have plagiarised, they could take actual, real world legal action against you and your company.
You may be doing your SEO stuff on your own, or you may have outsourced everything to a company likeUSEO, but in any case, never ever resort to doing these:
Publishing Copyrighted Content
This is usually not a big issue, except when it comes to publishing photographs. Web designers often use stock photographs and other pictures floating around on the Internet for sites they create. Don’t ever do this without checking the appropriate intellectual property licenses first. Copyright licenses usually mean you cannot publish the protected material without explicit permission from the original owner. Some intellectual property licenses are flexible and will let you publish with the right attribution. However, beware that some licenses prohibit commercial use of any sort. Keep that in mind when you next use a random photograph on your website. Make sure to check the terms and conditions in the intellectual property license. Using copyrighted material on your website without permission is illegal and could cost you more than a Google penalty.
Bad English
It all ultimately comes down to how good your content it. Articles that are too long, with too many keywords and are not grammatically or syntactically coherent will get marked as spam. Your SEO content should be well-written and not sound like it was generated by a 13-year-old, if you want to avoid a Google penalty for simply bad content.
Basically in the end what matters is how good your content is. SEO should only complement the best quality online material written for humans, not search engines, to avoid penalties and online ruin.