Image via WikipediaSearch engine optimization (SEO) is the process of improving the visibility of a web site or a web page in search engines via the "natural" or un-paid ("organic" or "algorithmic") search results. Other forms of search engine marketing (SEM) target paid listings.
Organic or algorithm based search results govern the effectiveness of search engine optimization. SEO is not limited to content result, however. Proper SEO takes images, local effects, videos, links, meta tags and industry related vertical searches into account. When a website is effectively optimized for search engines, the site starts to become an authority website and have a much higher web presence.
Search Engine Optimization is absolutely critical to generating online revenue and a strong client base. If a website is not properly optimized for any search engine index, it will be nearly impossible to find by your target demographic.
Meta-data refers to information about a website contained in the website code but not displayed by browsers. Meta-tags are the individual HTML elements which help search engines classify and rank web page content.
HTML page title: The HTML page title is one of the most critical factors for optimizing a web page for top search engine results. A unique page title should be crafted for each landing page within a site. The page title should correspond closely to the target content of the page.
Description tag: The HTML description tag contains information about a web page and its contents. HTML descriptions are often displayed as part of a search engine's results page. Most search engines place low importance on description tags. The description tag should correspond closely to the target content of the page.
Keywords tag: The keywords tag allows for additional placement of keywords into the HTML header. Most search engines place little or no importance on the keywords tag.
Other HTML elements: Other HTML elements include the H1 header tag, image alt tags, and body text. Very little importance is given to these elements, but including them could help to slightly increase placement in search results pages for highly competitive terms.
"Black Hat" Search Engine Optimization
Unscrupulous optimization techniques designed to gain an unfair advantage, or for purposes other than legitimate information retrieval, are called "Black Hat" techniques, and are usually penalized by the search engines.
Invisible text: Using white text on white backgrounds or other methods to hide keywords in order to increase rank or mislead crawlers.
Keyword stuffing: Adding extra keywords to meta-data or alt-tags.
Duplicate pages: Serving the same content from multiple hostnames.
Domain cloaking: Serving up different content to search engines than is served up to ordinary users. This technique is often used by the adult entertainment industry.
Link farms: Publishing web pages containing hundreds of links to your site in order to inflate inbound link popularity.
 Search engine optimization
 The Benefits of Search Engine Optimization
 University of Utah Office of Information Technology
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