Computer Technology: From Punch Cards to Supercomputers
Contents Early Computers 4 Analytical Engine 6 Codebreaking Machine 8 Mainframe 10 Video Game Console 12 Personal Computers 14 Wireless World 16 Supercomputers 18 Future Computers 20 Timeline 22 Glossary 23 Further Resources 24 Index 24
Early Computers Today computers are everywhere They are in toys cars and smartphones Computers started out as machines for counting things Some were used thousands of years ago Abacus The abacus was used in ancient China Each bead stood for a different number You put beads in rows to add up The abacus was invented 2,500 years ago 4
Slide Rule The slide rule is a ruler It has lines of numbers called scales You move the scales to do equations Punch Cards In the 1800s a special weaving loom was invented It used a punch card This was a card punched with holes It told the machine how to make patterns in the cloth Later the first computers used punch cards Read on to learn about how people invented new kinds of computers 5
