The document summarizes some important ideas and inventions that emerged during World War 1, including: The zipper was invented by a Swedish immigrant in the US and was adopted by the US army for uniforms and boots. After the war, the zipper became popular for civilian use. Time changes were instituted in Germany and the UK to conserve coal and energy. Pilots developed new communication technologies like headphones and microphones to communicate with each other and the ground. Nurses realized absorbent materials invented for clothing could be used as early sanitary napkins, and these later developed into Kleenex tissues.

1. Important ideas and inventions of the
First World War

2. The zipper
It was a Swede, Gideon Sundback, who created this. He emigrated
to the United States where he made this invention, which was
adopted by the US army. They incorporated it into his uniforms and
boots. After the war, the zipper became popular for civil use.

3. Time change
It started in Germany due
to the shortage of coal, to
save energy. It was
decreed that in Germany
on April 30, 1916 the
clocks that marked 23:00
should mark 24:00.
This system was adopted
by the United Kingdom
few weeks later.
Although it’s use was
stopped when the war
finished.

4. Communication with airplanes
Before the First World War ,
communication between
pilots, or between the plane
and earth, was impossible.
The aviators had to use
gestures and screams. This
promoted the invention of a
helmet in which the
headphones with a
microphone were installed.

5. The sanitary napkin and the kleenex
In 1914, Kimberly-Clark had
invented a material five times
more absorbent than cotton. In
1917, the US army started using
it when it joined the war. It was
intended to be used for the
clothing of health professionals,
but the nurses of the Red Cross,
in the middle of the war,
realized that it could be used for
feminine hygiene during
menstruation.
Shortly after the war they had the idea
of ironing this material to make it soft
and thin. After many experiments, the
kleenex was created in 1924.

6. The end