title: Most common locales for worldwide compatibility
body: <p>I don't think this has ever been asked on StackOverflow. I'm writing a C# program, but this question applies to any programming language under Windows 7.</p>
  
  <p>Since I want to make my program compatible with as many countries as possible (but with limited time at hand), what are the top 10 most common locales to test for? Since I'm using C#, this can be found by using:</p>
  
  <pre><code>CultureInfo.CurrentCulture.ToString()
  </code></pre>
  
  <p>As far as I know, these correspond with the items under: Control Panel -> Region and Language -> Format</p>
  
  <p>A no-brainer to test for would be "English - (United States)" (which under C# is "en-US").
  That's just one though - I'm looking for another 5-10 or so.</p>
  
  <p>The top 10 should also include 'variety'. For example, if they all used the period as the decimal point, that wouldn't be very helpful. I'd also want at least one to use the comma as the decimal point (as Europe, South America, Russia, and others do).</p>
  
  <p>Likewise, I'd want locales which use the '.', '/' and '-' as the date separator.</p>
  
  <p>So my original question is now a bit more complex, but potentially much more useful. I want the most used locales, but with a slight to moderate bias towards variety so that I can generalize testing more easily with a much better guarantee that they will work under untested locales.</p>