When you have new email click the Email dropdown at Read Email
You will see the unopened stuff you have received, and can choose either:
1) If you recognise it you can open and save or delete it.
2) If you think it is spam, click the Report Spam button on the bottom of the email window.
That will clear it, but if you find it was a long lost aunt in trouble, you can rescue it from the Spam folder, by clicking the This is Not Spam button.
The Report spam button is only available before the file has been opened. After that you will have to highlight and delete as with any other emails