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    <p><strong>Classes are useful because they can have methods and state/data</strong>. Generally speaking, if there is any data in your class, it's meaningless that you don't create any objects. However, you can implement a utility class which is composed of public static functions only. In such a case you don't have to create any object.</p> <pre><code>Class CMyHelper { public: static double calculateDistance(CPoint A, CPoint B); static double calculateArea(double length, double width); //... private: // You can even explictly say, I don't want make objects of this class. // You'll get a compile-time error if someone tries. CMyHelper(); CMyHelper(const CMyHelper&amp;); } CPoint A(100, 200); CPoint B(50, 100); //Call static method without instantiation CMyHelper::calculateDistance(A, B); </code></pre> <p><strong>In your case, there is no need to use static class, and friend class as we can see.</strong></p> <p>To me, friend class is the last thing I'll resort to. According to your description, you can make <code>move()</code> be the public method of <code>player</code> class since it's the player who actually "moves" instead of the <code>map</code>. Also, you need make it clear to us what's your <code>map</code> class does.</p> <p><strong>Edit:</strong> You can move coordinate of the player to player class if your map class is simpe enough to remove.</p> <pre><code>Class CPlayer { public: void move() { // moves up, down, left, or right // update m_position } } private: CCoordinate m_position; } </code></pre>
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    1. POShould I use a friend class here?
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    1. POShould I use a friend class here?
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    1. COYou can create a class and use it without "making objects" of it. These are called static classes in case you wanted to look into it a bit further.
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    2. COI see. So I should usually just use objects of the classes I create, even though in this example map.Move() makes less sense than player.Move()? I need Move() to access Map either way because the coordinates of the player are private data of Map. And thanks for the reply.
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    3. COYes, please use objects for your preference since in your case there isn't any need for a static class as I can see. You can make a map object part of your player's state so that in your player's move(), you can access coordinates. Again, what's inside map other than corrdinates? If nothing else, you can move it into player class and get rid of map...
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