History shows that Analog clocks use the traditional clock face – 3 moving hands in total, one of the hour, the minute and the second over an arrangement of fixed numbered dials that are placed in a circle and signify 12 hours of one day. The shorter hour hand can make exactly 2 revolutions in one day, whilst the longer minute hand makes one revolution every hour and the long but thin “seconds” hand makes one revolution per minute. Through our history, clocks have briefly used different configurations – the 10 hour clock during French Revolution and the 18th century Italian 6 hour clock. Both designs were abandoned in favour of standardised 12 hour Analog dial.
Sundials can also be considered as analogue clock. With over a 5 thousand year long tradition of using sundials (3500 BC – 1850s AD), this type of clock represent the longest lasting clock design of our history. This design delivers readings that are achieved following the sun’s shadow recorded by the sundial’s gnomon, but there are many obvious accuracy issues with this clocks use in modern times which is one of the main reasons they are not used today, the inability to be absolutely accurate, the manual calculation of daylight saving time, seasonal changes and the inability to work during night and during cloudy weather.
The rise of the digital era enabled us to gain access to very precise and reliable electronic clocks that display time with numeric displays. The two most common display formats are 24-hour notation (from 00-23) and in 12-hour notation where clock must also show AM/PM indicator. With each passing year, digital clocks gain ground over slowly disappearing analogue clocks. The display surface of this type of clock does not only have to be inside of small LCD, LED or VFD screens, but they can also be projected on either very large public surfaces or indoors for persons with imperfects vision.