©2012, TESCCC Change Grade 2 Unit 7, Lesson 1. Ripple Effect ©2012, TESCCC

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Change

Grade 2 Unit 7, Lesson 1

Ripple Effect

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Bicycle

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Communication

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Ancient times

In ancient times, people recorded information on clay or wax tablets using sticks.

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100-1400

Once paper, pens, and inks were invented, people copied books by hand. Most people did not have access to information.

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Printing

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1400Printing PressIn 1439, Gutenberg invented a machine that used movable type. This printing press made information more generally available.

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1714Typewriter

The first typewriter was invented in 1714, but it did not become widely used until the 1800s. Now we use computers to type information.

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1838Telegraph (and Morse Code)

The invention of the telegraph allowed people to send information long distances by using bursts of electricity over wires.

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1896TelephoneInformation could be exchanged immediately with the invention of the telephone.

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Telephone

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1927Television

With the invention of television in 1927, visual information could also be shared.

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1940sComputer

The first modern computers were invented in the 1940s. They were as big as a room. Now, all sorts of information can be exchanged immediately!

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