A Grandfather Clock generally stands about six and a half feet to eight feet tall. A grandfather clock is the common name used for a long case clock that stands in this height range. A grandmother clock is a long case clock that stands about six feet tall while a granddaughter clock is a logncase clock that stands about five feet tall. Both the grandmother and granddaughter clocks derived their name from the grandfather clock. The grandfather clock got its name from the song Grandfathers Clock by Henry Clay Work (1875). Work reportedly wrote the song after a visit to the George Hotel in England where an old longcase clock lost time everyday.

The longcase clock is a pendulum clock that stands on the floor. The first pendulum clock was built in 1656, but in 1670 William Clement encased both the pendulum and weights inside of a wooden case to diminish the effects of air current and improve precision. William Clements pendulum clock or the first long case clock saw the beginning of the Grandfather clocks. Robert Hooke was responsible for increasing the length of the pendulum to 39.1 inches, which takes precisely one second to oscillate. With this increased pendulum length and a new escarpment to handle the bigger pendulum, the longcase clock grew to just over seven feet tall.

Grandfather clocks were later encased with glass such that pendulum and weights can seen. The grandfather clock has played an important part in clock history as the most precise clocks for over two hundred years. But the grandfather clock has also captured the imaginations of many generations as being an elegant and fine piece of furniture. (Something the average desktop clock fails to do)