On page optimization is the stuff that you tweak on your own website for the benefit of SEO. Such things include properly using H1 tags, having clean and well-optimized html code, keyword density, etc.
Off page optimization is the stuff that is not on your own website, and therefore you don't have direct control over, which affects your website's search engine rankings. Such things include the number of backlinks you have on other sites, word of mouth, whether you have articles from your site syndicated in the blogosphere, RSS feeds, etc.
cscgal
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Neither one is more important than another. Off page SEO is what gets the search engines coming to your site. On page SEO is what gets the search engines correctly crawling and indexing your site, and plays a key role in what keywords you rank for and how much content the engines think you have. (And content is key)
SEO is the tehnique of ranking well in the search engines. If you rank well, you get free traffic from them.
cscgal
The Queen of DaniWeb
19,421 posts since Feb 2002
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