I have a mac computer and on the bottom of the screen (desktop) where you see the safari, calendar, photos, address book icons. There is a blue postal stamp icon, that I click to check my email. How can I removed this icon, but still be able to check my email? The reason I’m doing this is because I don’t want people (who use my Mac) to click on my mail icon and read my mail. To remove it, do I have to do something in system preferences?