Описание тега screen-orientation
Detects whether the screen is in portrait orientation (height > width) or landscape orientation (width > height), and switches between the two. This term is especially used in mobile devices, where applications are notified when the user rotates the device.
With the advancement of Mobile devices (including mobile phones, tablets, phablets, etc.) It became the implicit requirement of the user to have an application which can work both in landscape as well as portrait orientation. The screen-Orientation deals with the screens of mobile devices.
Questions related to managing applications while orientation change can be a part of this tag wiki.