Learn about Sitemaps here: https://www.sitemaps.org/protocol.html#xmlTagDefinitions

This plugin will install 2 new attributes under the SEO settings for your pages. 

• Change the Sitemap Priority to update your sitemap.xml file's <priority> setting for that page. 
• Change the Sitemap Change Frequency to update your sitemap.xml file's <changefreq> setting for that page. 

If you want to change the default settings that Concrete5 uses on all pages, go to the Structured Sitemap Settings page and change the default settings.  Any page that does not have the above attributes set will default to these settings.

If you uninstall the plugin, settings will revert to default of 0.5 priority and weekly changefreq.