White Hat SEO Vs. Black Hat SEO

Keyword stuffing. This involves the calculated placement of keywords within a page to raise the keyword count, variety, and density of the page. This is useful to make a page appear to be relevant for a web crawler in a way that makes it more likely to be found.

Example: A promoter of a Ponzi scheme wants to attract web surfers to a site where he advertises his scam. He places hidden text appropriate for a fan page of a popular music group on his page, hoping that the page will be listed as a fan site and receive many visits from music lovers. Older versions of indexing programs simply counted how often a keyword appeared, and used that to determine relevance levels. Most modern search engines have the ability to analyze a page for keyword stuffing and determine whether the frequency is consistent with other sites created specifically to attract search engine traffic. Also, large web pages are truncated, so that massive dictionary lists cannot be indexed on a single web page.

Hidden or invisible unrelated text. Disguising keywords and phrases by making them the same color as the background, using a tiny font size, or hiding them within HTML code such as "no frame" sections, alt attributes, zero-width/height divs , and "no script" sections. However, hidden text is not always spamdexing: it can also be used to enhance accessibility. People screening web sites for a search-engine company might temporarily or permanently block an entire web site for having invisible text on some web pages.

Meta tag stuffing. Repeating keywords in the Meta tags, and using meta keywords that are unrelated to the site's content. This tactic has been ineffective since 2005. "Gateway" or doorway pages Creating low-quality web pages that contain very little content but are instead stuffed with very similar keywords and phrases. They are designed to rank highly within the search results, but serve no purpose to visitors looking for information. A doorway page will generally have "click here to enter" on the page. Scraper sites Scraper sites, also known as Made for Ad Sense sites, are created using various programs designed to 'scrape' search-engine results pages or other sources of content and create 'content' for a web site.'pay-per-click ads'), or redirect the user to other sites. Some scraper sites have even outranked an original web site for its own information and organization name. The specific presentation of content on these sites is unique, but is merely an amalgamation of content taken from other sources, often without permission. These types of web sites are generally full of advertising (such as

Link spam Davison defines link spam (which he calls "nepotistic links") as "... links between pages that are present for reasons other than merit." Link spam takes advantage of link-based ranking algorithms, such as Google's PageRank algorithm, which gives a higher ranking to a web site the more other highly ranked web sites link to it. These techniques also aim at influencing other link-based ranking techniques such as the HITS algorithm.

Link farms. Involves creating tightly-knit communities of pages referencing each other, also known humorously as mutual admiration societies PDF (1.55 MiB)

Hidden links. Putting links where visitors will not see them in order to increase link popularity. Highlighted link text can help rank a web page higher for matching that phrase.

"Sybil attack". This is the forging of multiple identities for malicious intent, named after the famous multiple personality disorder patient "Sybil" (Shirley Ardell Mason). A spammer may create multiple web sites at different domain names that all link to each other, such as fake blogs known as spam blogs.

Spam blogs. Spam blogs, also known as splogs, are fake blogs created solely for spamming. They are similar in nature to link farms.

Page hijacking. This is achieved by creating a rogue copy of a popular website which shows contents similar to the original to a web crawler but redirects web surfers to unrelated or malicious web sites.

Buying expired domains. Some link spammers monitor DNS records for domains that will expire soon, then buy them when they expire and replace the pages with links to their pages. See Domaining. However Google resets the link data on expired domains.

Some of these techniques may be applied for creating a Google bomb, this is, to cooperate with other users to boost the ranking of a particular page for a particular query.

Using world-writable pages. Web sites that can be edited by users, such as Wikis, blogs that allow comments to be posted, etc. can be used to insert links to spam sites if the appropriate anti-spam measures are not taken.

Spam in blogs. This is the placing or solicitation of links randomly on other sites, placing a desired keyword into the hyperlinked text of the inbound link. Guest books, forums, blogs, and any site that accepts visitors' comments are particular targets and are often victims of drive-by spamming where automated software creates nonsense posts with links that are usually irrelevant and unwanted.

Comment spam. Comment spam is a form of link spam that has arisen in web pages that allow dynamic user editing such as wikis, blogs, and guestbooks. It can be problematic because agents can be written that automatically randomly select a user edited web page, such as a Wikipedia article, and add spamming links.

Wiki spam. Using the open editability of wiki systems to place links from the wiki site to the spam site. The subject of the spam site is often unrelated to the wiki page where the link is added. In early 2005, Wikipedia implemented a 'nofollow' value for the 'rel' HTML attribute. Links with this attribute are ignored by Google's PageRank algorithm. Forum and Wiki admins can use these to end or discourage Wiki spam.

Referrer log spamming. When someone accesses a web page, i.e. the referee, by following a link from another web page, i.e. the referrer, the referee is given the address of the referrer by the person's internet browser. Some web sites have a referrer log which shows which pages link to that site. By having a robot randomly access many sites enough times, with a message or specific address given as the referrer, that message or internet address then appears in the referrer log of those sites that have referrer logs. Since some search engines base the importance of sites by the number of different sites linking to them, referrer-log spam may be used to increase the search engine rankings of the spammer's sites, by getting the referrer logs of many sites to link to them.

Other types of spamdexing

Mirror web sites. Hosting of multiple web sites all with conceptually similar content but using different URLs. Some search engines give a higher rank to results where the keyword searched for appears in the URL.

URL redirection. Taking the user to another page without his or her intervention, e.g. using META refresh tags, Java, Java Script or Server side redirects.

Cloaking. Cloaking refers to any of several means to serve a page to the search-engine spider that is different from that seen by human users. It can be an attempt to mislead search engines regarding the content on a particular web site. Cloaking, however, can also be used to ethically increase accessibility of a site to users with disabilities or provide human users with content that search engines aren't able to process or parse. It is also used to deliver content based on a user's location; Google itself uses IP delivery, a form of cloaking, to deliver results. Another form of cloaking is code swapping, i.e., optimizing a page for top ranking and then swapping another page in its place once a top ranking is achieved.