If a collection is selected and opened in a tab, there are 3 variants to delete documents.
Single selection
In all three available views for documents, there is a button or an icon to delete a single record. After clicking the button and confirming a security query the document is deleted and the view is updated.
Multiple selection
In the table view, there is also the possibility to select checkboxes before each document or to select all records with the checkbox "Select All" in the table header. The button "Delete document(s)" will appear in the toolbar. After confirming the security query, the documents are deleted and you get the number of deleted items back via on-screen message.
Console mode
Of course also documents via the console mode can be deleted.
// Delete all documents with the city AGAWAM db.zipcode.remove({city: 'AGAWAM'});
In console mode, there is no confirmation prompt for deletion!
More about deleting documents via console can be found here http://docs.mongodb.org/manual/tutorial/remove-documents/