Previously, our ancestors measured time in different ways, for example: water clock, oil clock, sundial, obelisk. The first who knew that the day 24 hours were ancient Egyptians. They distinguished two parts in the day - dark and light time.
The first mechanical watches with a liquid escapement were made in Tang China in 725 AD by Yixing and Liang Lingzan. Then, every year, century, the clock became simpler and clearer. Nowadays there are electronic, radio frequency mechanical clocks. The most practical watch is an electronic one from such a watch you can even call to measure it, etc. The watch nowadays not only fulfills its function, but also people often use it as an accessory.
I believe that the clock has changed dramatically in its development.
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