These are some examples of the earliest tools wielded by humans.
What was the first machine that humans have ever used?
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Randy these are simple machines. Others include the wheel and the screw.
Dr Peter Lu claims spiral grooves on 2,550-year-old jade rings must have been made by a precision "compound" machine.
As the name suggests, compound machines comprise two or more machines with different motion that have been linked together to perform precision work.
Carved decorations on jades from ancient China are generally thought to have been made by hand, or with simple machines that worked with a single movement.
The ornamental jade burial rings reported in Science come from the so-called Spring and Autumn period (771 to 475 BC) and have been excavated from hoards and from tombs belonging to ancient officials and nobles.
The machine that carved the grooves would have linked rotational and linear motion, perhaps using a stylus suspended over a rotating turntable, says Dr Lu.
"The complex machine that created these spiral grooves may also be among the ancestors of the crank in China... sculptures to have mechanised a variety of agricultural processes such as milling and winnowing," Dr Lu writes in Science magazine.
Machines can be divided into two categories, simple and complex. Simple machines are tools that redirect force to make work easier, such as levers, pulleys, wedges, wheels, or inclined planes. The first evidence of simple machines dates back to 2 million years ago: fossils from Africa of early hominids called Homo habilis have been found with the first stone tools - hand axes made from chipped rocks which functioned as crude wedges.
The earliest Complex machines appeared much more recently. Machines which convert energy from a natural source into mechanical work are called prime movers. The first evidence of a prime mover dates back to around 100 BC when waterwheels first appeared in the Middle East. These were an adaptation of the older Noria, a wheel with buckets around the rim used by the ancient Egyptians and Sumerians to move water into irrigation canals. Windmills from Persia appeared by 650 AD, and both machines were used extensively throughout the world through to the Industrial Revolution.
(Disclaimer: the above answer does not necessarily reflect my belief)