Why the output is 10?

Question

import java.io.*;
public class Program
{
public static void main(String[] args)throws IOException{
int a;
a=System.in.read();
System.out.print (a);
}
}

//Why it is showing output as 10?
// What is the process which is going on in the internal memory?

Answer 1

But why the unfiltered stuff is always 10. When no input is given?

Answer 2

Thanks Martin Taylor