IF you’re using Gmail, the below should look familiar. The star on the email bar is just a way to favorite a message and store for later.
You can see all the emails you have ‘starred’ by clicking the ‘starred’ label. The ‘starred’ label exists under your Gmail Inbox here:
When you click the ‘Starred’ label it filters out all of your starred messages and you can see them in a list like this:
If you want more explanation see a video tutorial here