You can use class or typename in template parameters and they are equivalent, so the following two classes are exactly the same:

template <class T>
class C1
{
    T t_;
};

template <typename T>
class C1
{
    T t_;
};

As a matter of personal choice, I tend to use class for a template parameter that can only be a class because the template refers to a member.

template <class T>
class C2
{
    T t_;
public:
    void f()
    {
        t_.f();
    }
};

And I use typename for a parameter that is not used in this way. I feel it is a useful hint as to what kind of parameter is expected.