What is difference between sitemap.xml and xmlsitemap.php?

Selected answers from the Dumb SEO Questions Facebook & G+ community.

• 
  gaurav goutam: Hey friends,
  
  I have one question for you and hope I will get correct answer soon from your end.
  
  I have this website infiniteplastics when I check xml sitemap getting result, sitemap is missing. But When I can checking  ;xmlsitemap.php then sitemap appear so Please let me know:
  Google consider xmlsitemap.php sitemap formate? and it's working properly?
  
  Google getting access for all website pages?
  
  What is difference between sitemap.xml and xmlsitemap.php?
  
  sitemap.xml and xmlsitemap.php both working same way?
  
  Hope will hear you soon.
  
  Thanks ;
• 
  Federico Sasso: The sitemap name is just a name, naming it sitemap.xml is a common convention but nothing carved into stone.
  
  Your xmlsitemap.php could very well have the correct format (I cannot check, too many infiniteplastics sites around the world to pick your).
  
  As you might guess, Google need to know the name/location of your xml sitemap file. Two way to tell him: submit to it via Google Webmaster Tools (where you could also see a diagnosis in case of errors), and listing it in the robots.txt file (and other search engines could benefit).
• 
  Edwin Jonk: From the expert panel in this weeks SEO Questions hangout on air on 01:07:16 into the YouTube video: https://dumbseoquestions.com/q/what_is_difference_between_sitemapxml_and_xmlsitemapphp +gaurav goutam
  
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