Patrick Moran

16:9 (1.77:1) (16:9 = 4²:3²) is an aspect ratio with a width of 16 units and height of 9. Since 2009, it has become the most common aspect ratio for sold televisions and computer monitors and is also the international standard format of HDTV, Full HD, non-HD digital television and analog widescreen television (EDTV) PALplus.

Generally 16:9 is pronounced “Sixteen-Nine”, “Sixteen-by-Nine,” or “Sixteen-to-Nine.”

From Wikipedia.org