The bin includes the list of all your cuts. Indeed, each time you make a cut or delete an item/block, this cut/delete disappears from the sound and goes to the bin.
By using the combination "Ctrl" + "Sup" or "F5", the element or block is deleted but not moved to the bin.
By doing a right click on a cut, the following menu is displayed :
Play : plays the selected cut.
Rename : renames the selected cut
Paste : pastes the selected cut on the sound, where your playhead is.
Save as a new item : saves the selected cut as a master in the Browser.
Delete : deletes the cut from the bin.