A clock is a device used to tell time. Moving hands on the face of a clock point to the current hour, minute, and second.
There are three main types of clocks: mechanical, electrical, and atomic. All three must have a source of power and a way to display the time.
Mechanical clocks get their power from moving weights or springs. These parts are attached to gears, or toothed wheels. The gears are attached to the hands of the clock.
Electrical clocks get their power from electricity. Some of them have hands. Others have a digital display.
Atomic clocks measure time using the waves of energy given off by atoms. They were developed in the 1950s and are used by scientists in their work.
In ancient times people measured time by watching the position of the sun in the sky. The ancient Egyptians invented a form of clock called a sundial. Sundials cast shadows that move as the day passes.
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Throughout history, people have used various systems to organize the year into units such as days, weeks, and months. A calendar’s primary function is regulating and organizing human activities; the word derives from the Latin calendarium or calendra, “account book,” and kalendae or “calends,” the new moon and first day of the Roman month.
Unlike the day, the month, and the year, the week is not based on any astronomical event.
The modern calendar has 12 months of 30 or 31 days each (February has 28, sometimes 29). The calendar year has 365 days, which is about how long it takes the Earth to circle the Sun once. That makes it a solar calendar.
The oldest calendars were used to figure out when to plant, harvest, and store crops. These were often “lunar calendars,” based on the number of days it took the Moon to appear full and then dwindle away again.
Many calendars have religious origins.
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Everybody all over the world wears them- presidents, workers, students, pop stars… They will always be in fashion.
The first pair of jeans was invented by Levi Strauss.
The discovery of gold in California in 1848, made many ambitious young men rush there to strike it rich. Twenty-year-old Levi Strauss was one of them. He was a cloth seller in New York, and he took a few bolts of canvas cloth to sell on his journey to the West. In 1850 he reached the land of gold. It turned out that ‘up in the diggings’, where the miners worked, pants wore out very quickly. Levi took the canvas to a tailor and asked him to stitch a pair of pants. This is how the very first pair of jeans was made. The miners were the first persons in the world to wear jeans.
In 1886, Levi stitched a leather label on his jeans showing a pair of pants that were being pulled between two horses. This was to advertise how strong his jeans were.
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People use players everywhere, while walking, cycling, jogging, on the beach, in the bath, on planes, in bed – the list is endless.
I’d like to tell you the history of the Sony Walkman.
Akio Morita, the legendary head of Sony, once said how he had got his idea for the Sony Walkman. He used to go to the beach with his children, and the kids and their friends listened to loud music from boom boxes from morning till night. Morita asked his engineers to build a small radio or cassette player that would sound like a high-quality car stereo and yet could be attached to a person’s head.
The Sony Walkman was first introduced in Japan in 1979. It was a truly original product. The Walkman enabled people to listen to music of their choice, wherever and whenever they liked.
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