Protect ALL your windows. Remember that second floor and basement windows are as important as your first floor windows. Screens and storm windows are always an asset if properly secured. Wood or metal dowels laid in the track and screws set in the track to prevent the window from being lifted out are effective protective measures. Casement windows generally open and close by means of a gear operating handle and have a locking device which secures the window to the center post.
Some protection is offered by removing the crank handle from the operating mechanism.
Do not leave casement windows partially open as they can easily be forced. Louvered windows offer the same security problems as casement windows. Small slat louvers have the advantage that it is difficult to remove enough lites to gain entry easily. Make sure your louvered window locks are in working order. Keep your door closed and locked.