Clock systems are mechanisms used to measure and display time. They can be mechanical, like traditional pendulum clocks, or electronic, such as digital clocks. These systems typically consist of a timekeeping element, like a quartz crystal or gears, and a display to show the time, often in hours and minutes. Different clock systems serve various purposes, from simple wall clocks to complex atomic clocks that keep precise time for scientific research. Many modern clocks also include features like alarms, timers, and synchronization with global positioning systems (GPS) to ensure accuracy across different regions.