Difference between Static and Singleton Class in C#

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The major differences between Static Class and Singleton Class are below :

Static Class Singleton Class
Instances cannot be created Only one instance is created of a Singleton class in the class itself
Static class can have only static Constructor. Singleton class can have private constructor.
Static class is automatically loaded by the CLR. Singleton class is lazy loaded means it is created when user requests.
Inheritance of Static class is not allowed. As it contains a private constructor so you cannot inherit your singleton class but if you make it protected than you can inherit it but the base class will no more remain a Singleton Class.
Static class cannot implement Interfaces. Interfaces can be implemented here.
Passing to method: We cannot pass static class to method. The instance of Singleton class can be passed to a method.
public static class A
{
……// only static members
public static method1(){…..}
}
public B()
{
A obj = new A(); //error- cant create obj of static class
A.method1(); // method1 is accessed by class name
} 		public class SingletonExample
{
private static SingletonExample obj;
private SingletonExample(){}
public static SingletonExample Obj
{
get
{
if (obj == null)
{
obj = new SingletonExample();
}
return obj;
}
}
}

Take a Glance :

Singleton class only can create its own instance and restricting any other classes to create its instance, It is achieved by declaring the constructor private.
Many students asks me that i can make the constructor public or protected then also no error comes. So all those friends out there i want to ask you that you are creating Singleton Class so you must follow the Pattern. If you make it of other scope(not private) then you are not creating a singleton class.

The example given above is not thread safe, but you make it by creating a lock in the property.(take all the code in lock which is in get{…..}).