The G-Shock is a line of watches manufactured by the Japanese electronics company Casio, designed to resist mechanical stress, shock and vibration. G-Shock is an abbreviation for Gravitational Shock. The watches in the G-Shock line are designed primarily for sports, military and outdoors-oriented activities; all G-Shocks have a chronograph feature, 200 metre water resistance and an alarm, with either a digital display, analogue display or a combination of analogue and digital displays. Other features such as a countdown timer, world clock, and a backlight are included in most models. Newer high-end models in the line also feature GPS, directional, pressure and temperature sensors, radio-controlled time adjustment (known as WaveCeptor or Multi-Band) and Bluetooth time adjustment achieved via connecting to a smartphone via a dedicated application. History The G-Shock was conceptualised in 1981 by Casio engineer Kikuo Ibe when he accidentally dropped and broke a pocket watch given to him by his father. The G-Shock then was conceived as a watch which would have "triple 10" resistance, meaning it would have a battery life of 10 years, have a water resistance of 10 bar and could survive a fall of 10 metres. A team of three individuals was selected by Ibe which was known as "team tough". The team had assembled and tested nearly 200 prototypes but were still not able to achieve the conception criteria. During a visit to a playground, Ibe discovered that in a rubber ball, the centre of the ball doesn't suffer the effects of the shock during a bounce on a rough surface which gave him the idea to implement that concept into the watch. With that in mind, the team set out to develop a watch using such a concept and in April 1983, the first G-Shock, the DW-5000C, was launched. The shock-resistant design on the original G-Shock has 10 layers protecting the quartz timekeeping module, including a urethane rubber bumper, the stainless steel case, the hardened mineral glass watch crystal, the stainless steel screwed down caseback, and the "floating module" where the quartz mechanism floats free in a urethane foam cradle, with the outer buttons and LCD module attached with flexible cables. The strap of the watch is also designed to protect the module during a fall. Initial sales of the G-Shock line were sluggish in Japan as people preferred dress watches. In order to promote the G-Shock worldwide, the American division of Casio