XML Sitemap is a special file which contains all web pages of your site that you want to have been indexed by Internet search engines. It includes links to these pages, the importance of the link (priority), the frequency of update / visit, and the last modification date for a particular page. It looks like the figure below.
XML Sitemap (site map) helps and speeds up the whole site indexing by search engines. In this way, your blog quickly appears in search results, none of the parties shall not be omitted, and in addition due to the priority date of last modification, and search engine robots know exactly which pages of your blog is important and where there are changes and when these happened.
In this case xml sitemap is quite simple. Simply download the appropriate plugin, configure and run. Within few minutes, your blog will have xml sitemap.
This WordPress Plugin is responsible for creating a dynamic (real time) sitemaps of the blog is called Google XML Sitemaps. It supports all posts, pages, category pages and the tags and other custom created WordPress. Every time you create a new page or post, the plugin automatically rebuilds and update your sitemap, and report the change in the major search engines that support the protocol Sitemap: ASK.com, Google, MSN Search and Yahoo. You can download the plugin from the directory of WordPress. After installing and generating maps, you should add it to Google Webmaster Tools.