How Does Wi-Fi Work? , livre ebook

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HIGH-TECH SCIENCE AT HOME
How Does Wi-Fi Work?
by M. M. Eboch
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Edited by Leah KaminskiDesigned by Sara RadkaOriginal illustrations © Capstone Global Library Limited 2021Picture research by Eric GohlProduction by Kathy McColleyOriginated by Capstone Global Library Ltd
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Acknowledgements We would like to thank the following for permission to reproduce photographs: Alamy: Andrew Cheal, 23, TP, 4 (bottom right); Getty Images: Bob Rowan, 8, Hulton Deutsch, 14, Peathegee Inc, 42, Stringer/David Becker, 28; iStockphoto: Alfribeiro, 33, artbyjulie, 17 (map), Media Raw Stock, 39, pop_jop, 12; Newscom: WENN/Toasteroid/ZCHE, 29, ZUMA Press/JT Vintage, 13; Pixabay: Clker-Free-Vector-Images, cover (house icon), Fauno, 9 (all), 36 (all), paulnaude, cover; Shutterstock: Alex Murphy, 37 (bottom), Andrey Popov, 5, attraction art, 27, badahos, 11, Beatriz Vera, 31, Dr Project, 35, Gabor Tinz, 26, Kaspars Grinvalds, 25, Krunja, 18, LIORIKI, background (circuit board), mentatdgt, 24, metamorworks, 41, mStudioVector, 4 (top), muratart, 10, Ohmega1982, 44–45, ra2 studio, 21, 34, Reservoir Dots, 17 (antennas), sirtravelalot, 7, small smiles, 30, Svitlana Amelina, 4 (bottom left), taa22, 40, Vasily Makarov, 37 (top), View Apart, 20, ZadarmA Creation, 19.
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Contents
What is Wi-Fi? ........................................ 4
CHAPTER 1 No wires for Wi-Fi ................................ 6
CHAPTER 2 The roots of Wi-Fi .............................. 10
CHAPTER 3 How Wi-Fi works ................................. 18
CHAPTER 4 The many uses of Wi-Fi .................... 24
CHAPTER 5 Wi-Fi problems, Wi-Fi solutions ...... 32
CHAPTER 6 Wi-Fi in the future ............................ 38
Glossary ....................................................... 46
Find out more .............................................. 47
Index ............................................................ 48
Words in bold are in the glossary.
What is Wi-Fi?
What do a phone, a toaster and a dog collar have in common? These very different objects can share one high-tech feature. They can connect to the internet through Wi-Fi .
This is the Wi-Fi symbol. You see it everywhere. It is stuck to the doors of coffee shops. It glows on the screens of computers and tablets.
HIGH-TECH FACT
The original Wi-Fi logo was based on the yin-yang symbol.
Wi-Fi is a simple word with a complex meaning. To learn all about it, let’s look inside a laptop andsee how Wi-Fi works. Let’s discover the places Wi-Fi exists. And let’s see the amazing things Wi-Fi can do. Here’s a little preview:

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Some home appliances, includingfridges, now use Wi-Fi. With Wi-Fi , you can learn the top speed of a jet-powered go-kart. (It’s a bit more than 180 kilometres (112 miles) per hour.) With Wi-Fi, your fridge can order pizza from the supermarket. Yum! With Wi-Fi, you can find your lost dog. Here, boy!

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CHAPTER 1 No wires for Wi-Fi
Wi-Fi is sometimes called “wireless internet”. Through the internet, information is shared. The information can be words or pictures. It can be music or video. With Wi-Fi, a mobile phone or computer can connect to the internet and join in the sharing. The connection is strong and steady. Best of all, no wires are needed.
Wires, wires everywhere
Before Wi-Fi came along, devices were connected through wires. Computers had them sprouting from their back panels. These wires connected to other wires in the wall. They were then strung to wires on poles outside. These far-flung wires linked computers
in distant places.
In time, thousands of computers were connected. They formed a kind of giant web. This became the internet. Through this web of computers, information was createdand shared.
HIGH-TECH FACT
When you ask a questionon Google, your computerelectronically searchesabout 1,000 computers.On average, it takes 0.2seconds to get an answer.

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