Trash is the temporary storage location for deleted posts, pages, and comments in WordPress. It’s similar to your computer’s recycle bin or trash. If you accidentally deleted something, you can easily recover it from the trash.
To delete a post or a page, simply place the item in the Trash. When working inside of a post or page, you can quickly click the Move to Trash button located in the Publish module. You can also move a post or a page to the Trash by going to Posts and select selecting All Posts or Pages and selecting All Pages, and then placing your cursor over the Post or page, click on the Trash link that appears in the list of action options beneath the title at the top of the dashboard. You will be given the option to immediately undo the move. Items placed in the Trash will be permanently deleted in 30 days, or you can permanently delete the item immediately by going to the Trash section, hovering over the item, and selecting Delete permanently. Posts, Media, Pages, and Comments each have unique Trash folders to assist in protecting you from accidentally permanently deleting an item. If trying to restore an item, make sure to visit the proper Trash folder.