Hawk-Eye is a complex computer technology that is used in various sports--most notably, cricket--to track or project the trajectory of a ball. This interesting system charts the most probable path that a ball would take, and displays it on the screen, upon being synced with live action. Given the emergence of the Umpire Decision Review System (UDRS), Hawk-Eye is slowly becoming commonplace in cricket.

This technology was developed in 2001 at Roke Manor Research Limited of Romsey, Hampshire. Since then, this technology itself has spawned a company called Hawk-Eye Innovations Ltd, and has made strides in other sports like tennis as well.

No matter the sport, Hawk-Eye systems involve triangulating visual images and timing data provided by at least four high-speed video cameras located at different locations and angles around the area of play. A high-speed video camera and a ball tracker help this system process video feeds at very high speeds. Every Hawk-Eye system is also calibrated so as to take into account the playing area and the rules of the sport being analyzed.

Due to the fact that this complex system generates a graphic image of the ball path and the playing area, it provides visual information in real-time--which is why you see a Hawk-Eye trajectory of a ball almost immediately after a delivery is bowled! However, its backend database and archiving capabilities also make it possible to depict various other statistics visually. These include trajectories of sixes, fours, wagon wheels of batsmen, etc.

While the first instance of Hawk-Eye being used in a broadcast dates back to the England-Pakistan Test series in May 2001, the International Cricket Council (ICC) tried the now-famous UDRS only in the winter of 2008/09. Even today the usage of this technology is not mandatory and requires the approval of both teams involved in a series.

There's good reason for people to still doubt Hawk-Eye, which is said to have a 3.6mm margin of error. This is more accurate than any such system available, but it's still managed to fuel a lot of controversies in cricket. Most of these stem from the fact that this system cannot accurately judge the trajectory of a cricket ball immediately after it has bounced. Factors like pitch conditions and weather come into play here--and Hawk-Eye can, at best, provide a crude simulation of those. As a result, its universal acceptance still seems miles away!

Meanwhile though, this technology is being tried out in sports as diverse as snooker, tennis and football among others. But for now, human umpires are far more trusted to make tough lbw decisions. All in all, we cannot deny though that Hawk-Eye is a great add-on to the broadcasting realm--especially while tracking things like distance travelled by the ball, a bowler's pitch map, etc.