While pocket watches started to be produced in the late 16th century, they only showed the hour. It was not until 1680 that minute hands were added to clocks. The first second hand made an appearance 10 years later but did not become common practice for quite some time. The pocket watch replaced the old pendant time piece. This change is said to have occurred after Charles II of England introduced waistcoats. Due to wearing the watch in a pocket rather than being protected in a pendant, the shape was flattened and curved to avoid any sharp edges protruding and damaging clothing. The face was covered with glass in 1610 to protect the hands from damage.
During most of its history the watch was a mechanical device, driven by clockwork, powered by winding a mainspring, and keeping time with an oscillating balance wheel. These are called mechanical watches. In the 1960s the electronic quartz watch was invented, which was powered by a battery and kept time with a vibrating quartz crystal. By the 1980s the quartz watch had taken over most of the market from the mechanical watch. Historically, this is called the quartz revolution (also known as quartz crisis in Swiss). Developments in the 2010s include smartwatches, which are elaborate computer-like electronic devices designed to be worn on a wrist. They generally incorporate timekeeping functions, but these are only a small subset of the smartwatch's facilities.