Users hate being deceived. You hate being deceived. Google hates it too.
You may not think you are being deceptive, but are you sure? If you are, your site could be banned or penalized by Google.
If you are making your webpages for users, you likely do not have to worry about this guideline, but it is worth knowing what Google considers "deceptive" just to be sure.
Here are a few examples of techniques people use to deceive their users and search engines.
A link that says "click here to see pictures of cute kittens" should take a user to somewhere that is showing pictures of cute kittens, not a porn site. You should never automatically redirect a user to somewhere they are not expecting to go, or make deceptive links because of one main reason. Users hate that. You hate that. Google hates that too.
Posting fake reviews or falsifying info like fake ratings will get you penalized by Google. Using markup like rich snippets with such false information is a quick way to get penalized by Google.
If you have a website that has mostly the same content on two different domain names (something.com and someotherthing.com) then you are engaging in deception according to Google. This is called "duplicate content" and the Google help page covering this states...
"in some cases, content is deliberately duplicated across domains in an attempt to manipulate search engine rankings or win more traffic. Deceptive practices like this can result in a poor user experience, when a visitor sees substantially the same content repeated within a set of search results."
I have seen many people do this. It is best to have all your content on one website, not a million different ones.
The example websites in the image are basically the same content on three different domain names. The only thing that has been replaced is the name of the city. This is deceptive because the main content (a search function) is being shown on all websites, but the surrounding text is manipulated to try to rank for each city.
These are called doorway pages and users hate this, so Google hates this too. It is a bad technique that is mostly used by affiliate marketers to send visitors to a site that will pay them.
If someone clicks a Google result expecting Chicago real estate, they want to see useful results, like the houses for sale there, not just a search field to look for houses (the same search function that can be found on a million other websites).
A better way to do this would be to have a great informative site about a city you know and live in. Go out and take pictures of the houses you know are for sale, take pictures of the surrounding neighborhood to give your visitors more information than just the photos and text they can find on other websites. Google rewards such actions because they indicate a site is useful to its users.
by Patrick Sexton