Best Meta Tag for Seo Friendly

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Article Title           : Best Meta Tag for Seo Friendly
Author                  : Moh Sihabul Azhar
Website                 : http://desa-digital.blogspot.com/
Google+                 : http://plus.google.com/u/0/111985319566333964018/about
Rangking Alexa          : http://www.alexa.com/siteinfo/desa-digital.blogspot.com
Tool Analyzer		: http://www.scrubtheweb.com/abs/meta-check.html
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Dynamic meta tags (Not recommended)
 <b:if cond='data:blog.pageType == "item"'>
<title><data:blog.pageName/>: <data:blog.title/></title>
<meta expr:content='data:blog.pageName + data:blog.title + data:blog.pageName' name='Description'/>
<meta expr:content='data:blog.pageName + data:blog.title + data:blog.pageName' name='Keywords'/> </b:if>

OR

<meta content='DESCRIPTION' name='your-blog-description'/>
<meta content='KEYWORDS' name='your-blog-keywords'/>
<b:if cond='data:blog.pageType == "item"'>
<title><data:blog.pageName/>: <data:blog.title/></title>
<meta expr:content='data:blog.pageName + data:blog.title + data:blog.pageName' name='Description'/>
<meta expr:content='data:blog.pageName + data:blog.title + data:blog.pageName' name='Keywords'/>
</b:if>

OR
<b:include data='blog' name='all-head-content'/>
<meta content='DESCRIPTION' name='your-blog-description'/>
<meta content='KEYWORDS' name='your-blog-keywords'/>
<b:if cond='data:blog.pageType == "index"'>
<title><data:blog.pageName/> | <data:blog.title/></title>
<b:else/>
<title><data:blog.pageTitle/></title>
</b:if>

Normal meta tags (Recommended)
<b:if cond='data:blog.url == &quot;YOUR-SITE-URL&quot;'>
<meta http-equiv='Content-Type' content='text/html; charset=utf-8' />
<TITLE>YOUR-TITLE</TITLE>
<META CONTENT='YOUR-DESCRIPTION' NAME='Description'/>
<META CONTENT='YOUR-STE-OR-POST-KEYWORDS' NAME='Keywords'/>
<META CONTENT='AUTHOR-NAME-OF-SITE-OR-BLOG' NAME='Author'/>
<META CONTENT='YOUR-CONTENT-LANGUAGE' NAME='Language'/>
<META CONTENT='Select All to crawl contents easily' NAME='Robots'/>
</b:if>

Installing
Put below this code
<b:include data='blog' name='all-head-content'/>

Or
<head>
<meta tag><meta tag>
</head>