According to Google,
…we use the data in your Sitemap to learn about your site’s structure, which will allow us to improve our crawler schedule and do a better job crawling your site in the future. In most cases, webmasters will benefit from Sitemap submission, and in no case will you be penalized for it.
To read more about Sitemaps and why you should use them, go to the Original BlogByte on BrandByte.com

For WordPress:
I use ‘Google (XML) Sitemaps Generator’ for WordPress. Install the plugin from the ‘PlugIn’ option on your wordpress admin dashboard
The settings are pretty self-explanatory.
For Joomla:
I use the popular Xmap Component. Install the component and you are pretty much set.
Online XML Sitemap Generator
If you are unable to use the above options, you can also submit your site’s URL to http://www.xml-sitemaps.com/ (among others) and have a XML Sitemap generated for you. You then have to download the generated Sitemap.xml file and upload it to the server hosting your domain.

After creating a Sitemap.xml, you can either wait for search engines to find your site (and Sitemap) or be proactive about it by submitting your Sitemap directly to search engines. I like telling major search engines about the sites I help build, instead of waiting for them to find out.

Joomla: Components> Xmap

That’s it!
Obviously, Sitemaps are just a small part of what you can do to promote your site. The most efficient way to get social mentions and a high ranking on search engines is to provide great content.
Have you implemented an XML Sitemap for your blog or you plan to? Anything else to add?
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