Pointcloud2 vs PointCloud2Ptr

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Hi, the message i am subscribing to from a topic is PointCloud2, whereas my subscriber callback routine looks like this

void cloud_callback (const sensor_msgs::PointCloud2ConstPtr& cloud_msg){
 ROS_INFO("inside callback");
}

int main (int argc, char** argv) {
 ros::init (argc, argv, "cloud_sub");
 ros::NodeHandle nh;
 ros::Rate loop_rate(10);
 ros::Subscriber sub;
 while (nh.ok()) {
   sub = nh.subscribe ("input_cloud", 1, cloud_callback);
   ros::spinOnce ();
   loop_rate.sleep ();
 }
}

Will the fact that the callback type is a Ptr affect the message? How should i take in a Ptr in my callback with the fact that my message subscribed to is PointCloud2 datatype?