This is another tutorial discussing the negative on-page ranking factors.
If you want to follow the line, the previous tutorial was Cheating with page redirect.

The first thing I will start is not so harmful, but it matters when search engines (SE) are ‘spidering’ your pages. It is about using proper language without spelling errors.

Simply if you misspell a word, especially in the keyword you are optimizing for, can provoke indexing for that word. It happen really often some one to make this mistake and the only benefit that you can take is to accumulate visits from people who misspelled a word.
Even corrected this could be an issue for some time until the SE decide to change the search term for this page.
On the next example I am sure the creator of the site intend to write ‘software and hardware’ instead of:

It is funny but this site is on the second place when I am writing this article, by this misspelled keyword.

The next thing that is meddled with the words on your site are the words themselves. Here is a list with words which could stop AdSense showing on your site:

They are not “censured” by all search engines but Google, and many of these words now appear in normal context, without problems.

Other “bad” words are all targeted unrelated keywords on a page. This can decrease the importance of your real keywords.

About the language, try to not use words that change their meaning with combination with other words. As the previous I do not want to write them on the site so I will provide an image.

As you can see these are rather common words that can be used with different meaning from their “bad” sense, but as the search engines are not sinless your page or pages can get a proximity penalty.

It is rumored that there are certain phrases that have been associated with known spamming techniques and if you have such on your page, it could be penalized. Unfortunately there is no official list, and maybe this list is changing according to the modern Black Hat SEO tendencies.

So, when you make your sites, try to keep away from words with distorted double meaning, and also use spell checker.

We continue with the next tutorial which is Too frequent content changes.