vector of classes: what is the '*'?

[SheerSt]

In theory a simple question:

Normally when declaring a vector of classes in c++, I do something like the following:

#include <cstdlib>
#include <iostream>

#include <vector>

using namespace std;

class Class01
{
     public:
          int int01;
};

int main()
{
     vector<Class01 *> class01_vector;

     //...
}

So when declaring class01_vector in main(), I always have that '*' in between the <>'s, after the type: vector<Class01 *>. Does that '*' need to be there? What does it do? I've just always put it there because I was taught to, I've never really understood why. Thanks to all who clear this up for me, seems like it could be a pretty simple answer.

[hanst99]

It means that what you're storing are pointers, rather actual instances of the class. You should have covered pointers pretty much at the beginning of your course, as they are a pretty fundamental concept in C++ (although you're usually trying to avoid using them too much, writing useful programs completely without the use of pointers becomes, at some point, pretty much impossible).

[clanmjc]

It means that the vector contains pointers to Class01, without the * then the vector would just contain Class01 objects. It doesn't "need" to be there, but it can be, it depends on what you need to do.

[ne555]

It makes sense if you intend to store object of derived classes in that container.
Or if the container does not have the ownership