There are a number of techniques that webmasters have used over the years to try an outsmart Google. Today, many of these will get you banned, or at best penalized, so that your sites don't rank well, and consequently don't get the traffic you need.

1. Spam technique 1 - Sneaky redirects

Have you ever clicked on a search result in Google, but the URL you end up at is not the one listed in Google's results? = SNEAKY REDIRECT. Similarly, if you click on a link on a website and it takes you to a URL that is not the one referenced by the link = SNEAKY REDIRECT.

Not all redirects are sneaky. Some are there for good reason and don't try to deceive your visitors. Examples of this might include using your .htaccess file to redirect to affiliate links. This technique is widely used to hide affiliate links from visitors, or make URLs shorter and easier to remember. I doubt Google would include this as a sneaky redirect. Another safe type of redirect is a 301 redirect typically used to move a site from one domain to another.

If your redirect is not there to deceive your visitor, then it is probably OK.

2. Spam technique 2 - 100% Frame

This technique is a form of cloaking. On clicking a link in Google's search results, the page you are taken to has the URL of the page you expect, but a frame is used to show the contents of a completely different page.

The result is that Google's spider indexes and ranks the original page, but the page shown to visitors is a different one.

This is considered spam.

3. Spam technique 3 - Hidden Text / Hidden Links

Invisible text is easily done. Create the text or links in the same colour as the background colour. To the visitor, that text is invisible. To the search engine spiders that see only the raw HTML, they are there.

Often these can be spotted when you visit a web page by using the keyboard combination CTRL + A. This selects all text on the page, and hidden text can then be seen as they are highlighted by the browser.

Another form of hiding links is to hyperlink to a page using punctuation. e.g. linking a "." to a webpage. Its not invisible, but it is an attempt to hide a link from the visitor.

Another form of link hiding that I have seen is to have a phrase hyperlinked to several different documents. To the visitor, the hyperlink looks like a normal link, but move your mouse cursor along the link and you will see the address in the status bar at the bottom of your browser change to reveal different URLs for different parts of the phrase.

4. Spam technique 4 - Porn on expired domains.

A technique often used by webmasters is to buy old domains with existing PR and backlinks and using that PR to get ranked well for an unrelated topic.

This relates to all niches, not just Porn.

5. Spam technique 5 - Secondary Search Results / PPC

These are pages set up purely to collect PPC revenue without providing much relevant content of their own. A range of tools for scraping search engine results are available, but they will get you into trouble. For those still arguing that these tools do work, you are in the minority.

In a "leaked report" thought to originate from Google, the report also mentions sites that have directories setup to include DMOZ listings. However, it only specifies that these should be penalised if they contain PPC advertising e.g. Adsense. Those setup without Adsense are obviously providing the visitors with a service and should be ignored (links to relevant sites in your directory is value added for your visitor).

Think about the motives for setting up a directory like this. Is it for revenue, or for visitors? If the former, Google want it marked as spam. If it is the latter, you are OK for now.

6. Spam technique 6 - Thin Affiliate Doorway pages

Google considers affiliate pages that don't provide useful content to the visitor as spam. e.g. a page setup purely for ushering visitors to an affiliate program is considered spam, if that page does not provide the visitor with useful information or a useful service.

Pages that add value, and are useful to the visitors even if the affiliate links were removed are OK.

What this means is that you need to provide interesting, unique content on your pages. Create a page that will really interest your visitor, and then affiliate links are OK.

Again, ask yourself this question.

"If I removed all advertising from this page, would it be useful and/or interesting to a visitor?"

If yes, your page is safe. If not, it would be marked as spam by a rater.

To keep your affiliate sites safe:

Create every single page for the visitor.

Give the visitor a useful service.

For Example

Review something, then provide an affiliate link. That is fine.

Do surveys on the site and provide the survey results, and your affiliate links are probably fine.

Create a page that compares prices from different sources and your page is fine.

Create a page that reviews different merchants, and helps your visitor make the correct buying decision and you are fine.

Create unique, relevant and interesting/entertaining content on your site, and the affiliate links will be fine.

Also, don't use any technique that is only there for the search engine spider.

For your affiliate site to be safe, create a site that provides "a service" to your visitors.

"The report" says:

"Do not call a page affiliate spam when an affiliation is only incidental to the message and purpose of the website"

and

"Would this site remain a coherent whole if the pages leading to the affiliate were taken away?"

Is this last point an indication that you should have pages without affiliate links on them?

In my opinion, probably 99% of affiliate sites being built today are "thin", and won't do well in Google.

If a thin site gets spotted, it gets penalised.

OK, so how can you make sure your site is not labelled as thin?

Download the free eBook "Creating 'Fat' Affiliate Sites" to read more about this "leaked report", and how you can safe guard your affiliate sites. You can get the link in the resource box at the end of this article.