Search Engine Spam

Search engine spam is using un-approved methodology to "fool" a search engine, invariably with the intention of improving ranking.

With Google "intent" increasingly appears in relation to what they deem as search engine spam, it seems to be cumulative with penalties only applied when sufficient pointers exist to make the intent to spam beyond doubt.

The various search engines have their own take on what they deem spam, and these guidelines can be found below:

Problem is they're not particularly detailed so require a certain amount of reading between the lines which can lead to multiple interpretations, not helped by implementation/enforcement that can appear fairly lax.
When sites that are clearly in breach of the spam guidelines rank well it can make "compliant" webmasters feel more than a little foolish, and angry.

Much like SEO, search engine spam breaks down roughly into two areas on-page and off-page.

On-page mostly involves keyword stuffing through one form or another though it can also include excessive internal linking and/or hidden links.
On-page spam is less likely to be used these days due to it being both less effective and easy to spot and report by a competitor.

Off-page spam consists mostly in participation in links schemes of one kind or another and on the subject Google says:

"Don't participate in link schemes designed to increase your site's ranking or PageRank.
In particular, avoid links to web spammers or "bad neighborhoods" on the web, as your own ranking may be affected adversely by those links."

Google appears quite adept at identifying linkage patterns and will give sites the benefit of the doubt until there are sufficient pointers to remove any doubt that the intent behind the linkage pattern is to increase ranking or PageRank.

For further reading on search engine spam we recommend: