At the beginning of history, men only knew the day and the night. But over time, they began to observe the sun's movement, the moon and the tides, thus creating a principle of chronology.
The gnomons were the first watches created by men. It was kind of obelisk that, when illuminated by the sun or the moon, cast a shadow moving over hours.
This instrument had a small flaw: On rainy days or cloudy, you could not tell the time.
The first people who shared the day hours were the Babylonians and Chinese. For them, the day had 12 hours, each of which was equivalent to two hours we know today. Following the Egyptians and other Asian peoples divided by day in 24 hours.
In recorded history, we have the Sundial as the oldest instrument to mark the hours. In the Berlin Museum is exposed what is believed to be the most primitive instrument to measure the time. It is said that he belonged to the pharaoh Thutmose III of Egypt (1504-1450 BC).
The desire of evolution of man made he continued to conduct experiments and, therefore, Egypt came the "water clock" or Clepsidra, it was a container filled with water with graded walls and a small hole for water get out. Every two degrees drop corresponds to the passage of an hour. This instrument became popular throughout Asia and Europe until the sixteenth century.
In the eighth century, the Egyptians developed hourglass - also called hourglass - whose operation consisted of two glass cones connected by a small hole which regulated the sand passage placed on one party. When this sand was running out, it was just turn the instrument and process. They say that the Emperor Charlemagne had an hourglass 12 hours, and that Christopher Columbus used a half an hour.
The time mechanical measurement originated in religious communities, which had the need to regulate the times of prayer and worship. The first mechanical clocks did not show the time: made it sound. It was in Europe that this type was developed.
The mechanical manufacturing techniques clock were appearing at the time of the maritime discoveries, after the end of the Middle Ages, because there was a need to understand more and more the time accuracy. This process was gradual and based on the evolution of the clock sound.
Finally, given that the first clock marking the time the way we know it today would have been manufactured in 1386 by Henry Vicky, under the order of the King of France, and is in the Science Museum in London. It was from him that has come up to the multitude of models we know today, such as quartz, the clock, the atomic and finally digital.
The Brazilian who invented the airplane, Santos Dumont also made his contribution: he invented the wristwatch. Since he could not use his hands during the flight, held a Cartier watch in the arm. He later commissioned Cartier plant their own watch to be worn on the wrist.
Clock Quartz: Quartz clock marked the watch industry in the late twentieth century. The use of mechanical vibrations of the mineral, researched since the 1930s, is widespread in the 1960s, making the most accurate clocks. In the search for more precision, in 1967 we started to use the electromagnetic radiation of the cesium atom.
Digital Clock: The Digital Clock is a type of clock that uses electronic means to track hours. It uses a piezoelectric crystal capable of generating electric pulses at a constant frequency (usually 50 or 60 Hz). Being a fairly cheap and simple device, are associated with many other electronic devices.
Atomic Clock: The atomic clock allows time measurements up to 100 thousand times more accurate than conventional devices. Enable experiments that were once considered impossible, especially in the field of astronomy and gravitational waves. As a clock pendulum, the atom can be stimulated externally (in the case of electromagnetic waves) so that your energy fluctuate regularly, eg every 9,192,631,770 oscillations of the cesium-133 atom clock believes that spent second. The most used elements in atomic clocks are hydrogen, rubidium, and especially cesium. It is considered the most accurate clock built by man, delaying only 1 second every 65,000 years. Thus the International System of Units (SI) matched a second 9,192,631,770 radiation cycles, corresponding to the transition between two energy levels of the cesium-133 atom.