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Greg, While you're in the learning stages, it can be easiest to think of one keyword--one page. You also have to consider how competitive the keyword is and how strong your competitors are for each keyword.  With that in mind, newer sites will often choose keywords that don't have the most activity because it can be very difficult to rank for those.   Also, the keyword meta tag is essentially obsolete for google ranking purposes so you'll have to go deeper to optimize for the terms you want to rank for. I recommend you read through  The SEO Guide From Moz to get thing rolling for your site.