Q:

what the need of using single and float keywords separately . when we have to use single in the real time scenario?

when i am working with single and float in c#, i am getting the same result for both, then why 2 separate keywords.
namespace WpfApplication1 {
    /// /// Interaction logic for MainWindow.xaml ///
    public partial class MainWindow : Window {
        public MainWindow() {
            // Console.WriteLine("correct1");
            float a = 10.6f; Single b = 10.6f;

            Console.WriteLine("correct"+(a/b));
            InitializeComponent();
        }
    }
}

A:

what the need of using single and float keywords separately . when we have to use single in the real time scenario?

The two keywords are interchangable.
float is actually provided by the C# language, and is an alias for System.Single.  You can't use Single by itself, as its not merely a keyword, but the System.Single type.  This requires a using System; at the top of your file or fully qualifying it.  float, on the other hand, is a language provided keyword, and will work in any scenario, without bringing in the namespace.
This is also the case with int/System.Int32, double/System.Double, etc.

A:

float is an alias for single. 
float C# - MSDN

(Remember that float is an alias for the System.Single type.)

