Tagging your post content increase not only your pageviews but they also get internally linked and when some one click on the tag in tag cloud then it shows all the post related. now when you write a post it is not possible to tag each important keyword at the same time . But here is some thing that you can do .
you can install the Wp-auto tagger plugin and this will help you to Tag your post content directly when you save this .This plugin uses the Yahoo API to suggest tags based on the post content. The plugin will add a `Suggest Tags` button to the `Write Post` page sidebar.
you can download this plugin or directly install by searching Wp-autotagger .this plugin is written by idope. but keep in mind if you have nay other plugin installed for tags like simple tags then this might not work properly.
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