INTRODUCTION: TECHNOLOGY

Technology is the practical application of knowledge (science) and skills (techniques) to create objects or solutions which satisfy our needs or solve our problems.




FIRST MACHINES

 



1.- THE FIRST MACHINES.
People invented the first machines a long
time ago. They were simple tools made of
stone, wood, or bone.
About two million years ago people made
stone axes with wooden handles. They used
these tools to cut wood. People also used
stone and animal bone to make knives and
arrows. To shoot their arrows they used
bows made with long pieces of wood.

People used simple levers to move heavy
objects like rocks. They put one end of a
long stick of wood under a big rock, and
they put a small rock under the stick. When
they pushed on the other end of the stick,
the big rock moved.
About 7,000 years ago people started
farming for food. They invented new
rnachines, like plows, and used animals to
make work easier. Some farmers used long
levers to get water from rivers. They also
built canals to get water for their plants.
About 5,000 years ago people started
making metal tools. These tools were
better than stone or bone tools.
 
2.- THE WHEEL
The wheel is one of the most important
inventions in history. About 5,500 years ago
potters used the first wheels to make clay
pots. They put wet clay on a wooden wheel.
Then they turned the wheel to make a nice
round pot.
Before people had wheels to move heavy
objects, they used rollers. The rollers were
made from tree trunks. Then people made
carts and chariots with wooden wheels.
They connected the wheels with a long bar
called an axle
Today there are lots of machines with
wheels. We can see wheels on cars, bicycles,and skateboards.
There are also wheelchairs for people who can't walk
easily. Can you think of more machines that have wheels?
 (The London Eye is a very big wheel. It´s 135 meters high.You get a great view of London from the top).


3.- RAMPS AND CRANES.
Ramps are useful because they help us lift
objects more easily. More than 5,000 years
ago the Ancient Egyptians used ramps to
build pyramids. The Great Pyramid at Giza
is the biggest pyramid in the world. It's 138 meters high.
The Egyptians used rollers to move large
blocks of stone up the ramps. They needed
lots of workers because the blocks were
very heavy.
About 2,500 years ago the Ancient Greeks
used big cranes to build temples. The cranes
were made of wood, and they had many
ropes and little wheels called pulleys. First
the workers tied a rope to a block of stone.
Then they put the rope around the pulley.
They pulled the rope and lifted the block.
The work was easier with cranes, so the
Greeks didn't need as many workers as
the Egyptians.