Instance() in Singleton Class Question

    I am curious to ask. Why do you need to use Instance() function?
You can always use Singleton() function and ~Singleton() function.
Execute Instance() function will start to execute Singleton() function
before it returns back to Instance() function. The program exited
before it will not execute ~Singleton() function. You must use
Terminate() function manually to clear dynamic memory otherwise leak
memory can occur. It is not worth practice.
    Read Note 1 and Note 2 inside main() function. Note 2 does its own
job to execute ~Singleton() function before program exits. Note 2 is
always useful when you want to use only one instance (one object such
as keyboard, mouse, floppy drive, etc)...

#include <stdio.h>
#include <stdlib.h>

class Singleton
{
public:
    static Singleton* Instance(); // Why do you need it?
    void Terminate(); // Why do you need it?

    static void Print();

//protected:
    Singleton();
    ~Singleton();

private:
    Singleton(const Singleton&);
    Singleton& operator= (const Singleton&);

    static Singleton* pinstance; // Why do you need it?
};

Singleton* Singleton::pinstance = 0;

Singleton* Singleton::Instance ()
{
    if (pinstance == 0)
        pinstance = new Singleton;

    return pinstance;
}

void Singleton::Terminate ()
{
    if (pinstance != 0)
    {
        delete pinstance;
        pinstance = 0;
    }
}

Singleton::Singleton()
{
    printf("Constructor\n");
}

Singleton::~Singleton()
{
    printf("Destructor\n");
}

void Singleton::Print()
{
    printf("Test\n");
}

int main()
{
    // Note 1
    Singleton & ref = * Singleton::Instance();
    ref.Print();
    ref.Terminate();

    // Note 2
    Singleton s;
    s.Print(); // ( Singleton::Print() is same as s.Print() )

    system("pause"); // Function comes from Microsoft Visual C++ .Net

    return 0;
}