First Stage Recycle Bin - When you delete an item from a site or sub-site it goes to the Recycle Bin (also called the user's Recycle Bin) of that particular site and stays there until you restore it back or the retention policy expires (deleted after a set number of days, by default it stays for 30 days) or you delete it from there, in that case it goes to the Site Collection Recycle Bin. You can view a site's Recycle Bin by clicking on the Recycle Bin link in the Quick Launch.