When should you use a class vs a struct in C++?

Question

In what scenarios is it better to use a struct vs a class in C++?

Answer 1

When would you choose to use struct and when to use class in C++?

I use struct when I define functors and POD. Otherwise I use class.

// '()' is public by default!
struct mycompare : public std::binary_function
{
    bool operator()(int first, int second)
    { return first < second; }
};

class mycompare : public std::binary_function
{
public:
    bool operator()(int first, int second)
    { return first < second; }
};