Casio was one of the earliest manufacturers of digital and analog quartz watches. During the 1980’s Casio released a wide variety of quartz watches and calculator watches. The G-Shock line was introduced in 1983. It was designed for sports. The initial concept was that the watch’s battery can last 10 years, be water resistant up to 10 bars, and survive a 10 meter drop. The shock resistant design has 10 layers protecting the quartz mechanism. This watch became wildly popular through the 90’s and to this day. Casio continues innovating watches, with atomic clock synchronization, solar power, cold weather resilience, moon graphs, and a tidal wave recorder on a variety of models.