Final answer:
The Atomic Standard uses an atomic clock, which is extremely precise due to the vibrations of cesium atoms and defines the second, the fundamental unit of time.
Step-by-step explanation:
The kind of clock that the Atomic Standard uses is an atomic clock. This type of clock relies on the vibrations of cesium atoms to keep time with incredible precision, typically to better than a microsecond per year. Atomic clocks are the backbone for the current definition of the second, which is the fundamental unit of time. They work by supercooling cesium atoms in a vacuum chamber and then bombarding them with microwaves at a frequency that causes them to make an electronic transition to a higher energy state. This state decay then emits radiation at the frequency that defines the second.
While other clocks such as analog clocks, digital clocks, and sundials are used for everyday timekeeping, they do not offer the same level of precision as atomic clocks. Analog and digital clocks represent time using hands or digits, respectively, and sundials use the shadow cast by the sun to indicate time, requiring adjustments based on location and daylight saving time.