When you join Google+, you will very quickly become familiar with this.
The bell icon in the centre will often have a little red box with a number inside it. That tells you instantly how many notifications you have.
Clicking on it, pulls up a box like the one below.
This allows you to view individual notifications, all from within the little box.
All good so far. Well, not really. The little box is little and doesn’t do a lot of posts justice. So here is a little tip to help you.
At the top of the box is a link called ‘Google+ notifications.’ Click on that and you will see all of your notifications in your Home stream.