IN THIS PRESENTATION LEARN ALL ASPECTS OF CELL PHONES I HOPE YOU ENJOY

2. The cell phones
Valeria García
Javier Duarte

3. History of cell phones

4. Goes back to the beginnings of World War II, is
born by the need of remote communication, its
promoter was the Motorola services company in
the military, it was only a matter of time before
the technologies of Tesla and Marconi and join
gave birth to the radio-telephone
communication.

6. That is a cell phone?

7. The cell phone is a wireless electronic device
that allows to have access to the network of
cellular or mobile telephony. His principal
characteristic is his portability, which one allows
to communicate from almost any place. The
principal function is the communication of
voice, as the conventional telephone.

8. Why are they called cell phones?

9. The systems of wireless telephony divide in cells
or cells, it is for this that the devices of mobile
telephony know also as cell phones

10. The first cell phones
This one is the Motorola
DynaTAC 8000X and first
appeared in 1983, the cell
phone was used only to
communicate and had a
battery charge lasted only a
few hours.

11. Did you know?

12. Martin cooper is the creator of the cell
phones

13. The evolution of the cell phones

14. They were evolving in less than one decade they
have had many notable changes: now you
assemble several possibilities of communication
and entertainment: one or two lines,
transmission and receipt of voice, etc. In
addition they reproduce music

16. Some companies of cellular telephony

18. Advantages and disadvantages

20. Advantages
• Talk to whoever you want where you want to walk
• You can quickly call in case of an emergency
• Facilitates communication with people who do not
have close
• It is comfortable
• The can carry around
• You find out what's happening in the world
• You can take photos
• listen to music
• You can send text messages, images or videos

21. Disadvantages
• Walk with a vice if you know not to use limits
becomes
• The rates they charge are expensive
• You get used to it and returns you need
• Not all people make good use of the
• By providing information sometimes people
do not reason

22. Negative effects of the cell phone

23. The use of the mobile telephone, beside
communiqués being kept and in the wave of the
21st century, brings side effects in which, in case of
being informed, we do not even think. And the
worse thing; as the tobacco concerns the "passive"
users and big hurts the environment. Did you know
that the battery of your mobile can contaminate
600.000 liters of water? Did you know that the
radiation of your mobile overcomes 3 million times
the radiation of the Sun? Not speak about the Car
Crashes while a "call" was attended...

24. Since the cell phone works

25. The cell phone works by means of the union of a
network of stations transmitting-receiving of
radio, so called towers; (base station, which this
formed by a tower; a small building where the
equipment of radio is) and a set of telephone
central offices.