Minecraft wiki entry for Inventory, associated text: Pressing drop while the cursor is hovering over an item in the inventory or a container drops one item. Holding Ctrl and pressing drop while hovering over a slot in the inventory or container that has one or more items drops the entire stack of items. While venturing without the full inventory open, the same can be applied for the selected item(s) from the hotbar. Items can also be dropped into the world by clicking outside the inventory window while holding an item with the cursor.