stays balanced by shifting the
A professional skateboarder
wears a helmet and padding
while performing a difficult stunt
on a closed-off ramp. Skateboarders
should stay safe at all
times.
Sitting Bull was a leader of the
Sioux people. He was known for
his bravery and wisdom.
BRITANNICA STUDENT ENCYCLOPEDIA Skateboarding 93
feet and body. Many young people enjoy
skateboarding as a hobby. It is also an
organized sport. The best skateboarders
can invent and perform difficult tricks.
Most skateboards are about 32 inches
(81 centimeters) long and 9 inches (23
centimeters) wide. The back end of a
modern skateboard is bent upward. This
is called the kicktail. The wheels are
made of a special kind of tough plastic.
Skateboarding Styles and
Events
The two main styles of sport skateboarding
are vertical (or vert, for short) and
street style. Vertical skaters jump off
ramps or perform in U-shaped riding
surfaces called half-pipes. They do tricks
in midair. Street-style skaters perform in
city environments. They ride their skateboards
over objects such as steps, railings,
and ledges.
These styles of skateboarding have been
organized into competitions. Events are
held in Australia, Brazil, Canada, and
the United States, and throughout
Europe and Asia. Skateboarding is also a
part of the televised sports festival called
the X Games.
History
The first skateboarders made their own
boards in the early 1900s. The simplest
homemade skateboards had roller-skate
wheels attached to a board.
Skateboarding became popular in the
early 1960s. It developed among surfers
in California, in the United States. Surfers
use special boards to ride on waves in
the ocean. When there were no good
waves for surfing, some surfers changed
their boards. They added wheels so they
could ride on the sidewalks near the
ocean. Skateboarding was even called
sidewalk surfing.
The first skate parks were built in the
1970s. They had slopes and banked
surfaces for sudden turns and stunts. But
some skateboarders chose to skate in
empty swimming pools. This was the
beginning of vertical skateboarding.
Soon skateboarders started riding in
half-pipes. Street-style skating started in
the 1980s.
Skating
Skating is a form of sport that has three
main types: ice skating, roller skating,
and skateboarding. Ice skating is the
American
skateboarder
Tony Hawk
helped make
the sport
popular in the
1980s and
1990s.
Many people enjoy skating as a casual
form of entertainment. For others it is a serious
sport.
94 Skating BRITANNICA STUDENT ENCYCLOPEDIA
oldest form of skating. Thousands of
years ago people used animal bones as
skates to cross frozen bodies of water.
Modern ice skates are shoes or boots
with metal blades attached. Ice skating
has three main divisions: figure skating,
speed skating, and ice dancing. The
team sport of ice hockey also involves
skating.
Roller skates have wheels instead of
blades. Indoor types of roller skating
include roller dancing, figure skating,
and speed skating on hardwood, plasticcoated
tracks. Roller hockey is usually
played outdoors. In the 1980s roller
skaters started to use in-line skates, or
Rollerblades. They are faster than traditional
roller skates.
Skateboarding is a popular sport that
began in the U.S. state of California in
the early 1960s. Young people started
skateboarding on pavement near beaches
when the ocean was too calm for surfing.
A skateboard is like a small surfboard
with wheels. Skateboard parks
provide a variety of slopes and surfaces
for riding.
#More to explore
Hockey, Ice • Ice Skating • Roller
Skating • Skateboarding
Skeletal System
The collection of bones in an animal’s
body is called a skeletal system, or skel-
Fish, birds, reptiles, and mammals are four types of animals that have skeletons inside
their bodies. The skeletons of a perch, a chicken, a crocodile, and a cow are shown.
BRITANNICA STUDENT ENCYCLOPEDIA Skeletal System 95
eton. Mammals, birds, reptiles, amphibians,
and fish have skeletal systems.
Insects and shellfish do not have skeletons
inside their bodies. Instead they
have hard, outside coverings called
exoskeletons. The skeletons of corals and
sponges are made of stony minerals, not
bone. Some animals, such as jellyfish,
have no skeleton at all.
The human skeletal system has more
than 200 bones. The hard, stiff bones of
the skeleton support the whole body.
The skeleton also protects the soft
organs inside the body. In addition, the
skeleton works with the muscles to allow
the body to move.
Support
The most basic job of the skeletal system
is support. For example, the spine, or
vertebral column, supports the entire
upper part of the body. The human
spine lets people stand and walk in an
upright position, or posture. Humans
enjoy great advantages over other animals
because of this posture. Because
humans use only their legs for walking,
their arms are free for useful activities,
such as using tools.
Protection
The second major job of the skeletal
system is protection. The skeleton’s rigid
structure protects the body’s soft organs.
For example, the rib cage formed by the
spine and the ribs protects the heart, the
