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JOAN CARTAN-HANSEN: HI, I'M JOAN

CARTAN-HANSEN.

AND WELCOME TO SCIENCE TREK-THE

WEB SHOW.

AND WELCOME TO THE OFFICES OF HP

HERE IN BOISE.

JOINING US NOW TO ANSWER YOUR

QUESTIONS ABOUT COMPUTERS ARE

TIM ANDERSEN AND FLOSSIE ERBEN.

THANK YOU BOTH FOR BEING HERE.

TIM ANDERSEN: THANK YOU.

FLOSSIE ERBEN: THANK YOU, WE'RE

HAPPY TO BE HERE.

CARTAN-HANSEN: OKAY LET'S GO TO

YOUR QUESTIONS.

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NORAH: HI I'M, MY NAME

IS NORAH, MY QUESTION IS HOW DO

COMPUTERS WORK?

ERBEN: SO COMPUTERS ARE BUILT OF

MANY DIFFERENT PARTS AND

COMPONENTS, YOU HAVE EVERYTHING

FROM YOUR CIRCUITRY CHIPS

THAT DRIVE THE PROCESSOR.

YOU HAVE FANS THAT KEEP THE

DEVICE COOL, YOU HAVE WIRES THAT

CONNECT PIECES TOGETHER, YOU

HAVE

HARD DRIVE WHERE YOU STORE YOUR

DATA, YOU HAVE A KEYBOARD IN

WHICH YOU CAN GIVE INSTRUCTIONS

TO THE COMPUTER.

YOU HAVE A MONITOR SO THAT IT

CAN DISPLAY WHAT YOU'RE ASKING

IT TO DISPLAY.

AND IN SOME CASES YOU HAVE

THINGS LIKE A MOUSE TO HELP

DRIVE DIFFERENT PORTIONS OF THE

COMPUTER.

HERON: HI MY NAME IS HERON AND

MY QUESTION IS, HOW DOES LIKE

THE KEYS ON THE COMPUTER WORK?

ANDERSEN: SO EVERY KEY ON YOUR

KEYBOARD HAS UNDERNEATH IT A

CIRCUIT AND WHEN YOU PRESS THAT

KEY YOU COME DOWN, YOU PUSH THAT

KEY IT PUSHES DOWN AND TOUCHES

THAT CIRCUIT AND CONNECTS IT SO

THAT AN ELECTRICAL SIGNAL GOES

THROUGH THE CIRCUIT AND ITS SENT

TO THE COMPUTER AND TELLS THE

COMPUTER EXACTLY WHICH KEY YOU

PRESSED.

BY THE WAY, WHEN I WAS IN

COLLEGE WE WROTE A KEYBOARD

DRIVER FOR A VERY SIMPLE

COMPUTER AND YOU HAD TO, SO THE

KEY COMES DOWN AND THE

COMPUTER'S RUNNING SO FAST THAT

IT'LL HIT THAT CIRCUIT AND

BOUNCE.

YOU DON'T KNOW THAT IT'S

BOUNCING; YOU THINK YOU JUST

PRESSED THE KEY AND YOU JUST

CONNECTED THE CIRCUIT, BUT IT

ACTUALLY BOUNCES UP SO IT

DISCONNECTS THE CIRCUIT AND

BOUNCES BACK AND CONNECTS THE

CIRCUIT BACK UP.

AND IT DOES THAT PROBABLY SIXTY

PLUS TIMES BEFORE IT SETTLES,

AND THEN WHEN YOU RELEASE THE

KEY IT DOES THE SAME THING JUST

KIND OF IN THE OPPOSITE.

SO IF YOU DON'T HANDLE THAT, YOU

KNOW, YOU CAN HANDLE IT AT THE

HARDWARE LEVEL, BUT IF YOU DON'T

HANDLE IT AT THE DRIVER LEVEL

YOU'LL GET LIKE A HUNDRED AND

SOMETHING KEY PRESSES OUT OF

EVERY KEY PRESS THAT YOU THINK

YOU'RE MAKING.

SO YOU HAD TO WRITE A DELAY LOOP

BASICALLY IN YOUR KEYBOARD

DRIVER TO DELAY ONCE YOU HIT THE

INITIAL CONTACT YOU DELAY

LOOKING FOR MORE CONTACTS UNTIL,

YOU KNOW, HUNDRED MILLISECONDS

OR SOMETHING LIKE THAT.

KELSEY: MY NAME IS KELSEY AND I

GO TO JEFFERSON ELEMENTARY IN

POCATELLO, IDAHO AND MY QUESTION

IS WHY DID THEY INVENT

COMPUTERS?

ERBEN: THEY INVENTED COMPUTERS

TO HELP US AND HELP HUMANS DO

THE CONTINUAL MATHEMATIC

EQUATIONS AND COMPUTATIONS OVER

AND OVER AGAIN.

THE HUMAN MIND GETS BORED AND SO

SOMETIMES WE START MAKING

MISTAKES, SO IT WAS EASY TO HAVE

THIS PROCESS AND THIS COMPUTER

TO CONTINUE TO ANSWER THOSE

QUESTIONS FOR US.

BRADEN: HI MY NAME IS BRADEN AND

MY QUESTION IS HOW DOES A

COMPUTER MEMORY CHIP WORK?

ANDERSEN: SO A COMPUTER MEMORY

CHIP WORKS BY STORING ELECTRICAL

CHARGE ON THE CHIP, IN A

PARTICULAR LOCATION THAT

CORRESPONDS TO A BIT AND THERE'S

BILLIONS OF BITS WORTH OF

INFORMATION ON EVERY COMPUTER

MEMORY CHIP AND SO THAT CHARGE

IS STORED ON THE CHIP IN SEVERAL

DIFFERENT PLACES, BILLIONS OF

DIFFERENT PLACES AND IF THE

CHARGE IS PRESENT YOU CONSIDER

THAT TO HAVE A BIT VALUE OF ONE

IF THE CHARGE IS ABSENT ITS GOT

A BIT VALUE OF ZERO.

SAM: HI MY NAME IS SAM AND MY

QUESTION IS IS HOW GOOGLE GETS

ALL THEIR ANSWERS FOR QUESTIONS?

ERBEN: GOOGLE GOES ABOUT

GETTING, ITS A SEARCH ENGINE AND

IT GOES ABOUT GETTING ALL OF ITS

ANSWERS BY SEARCHING THE WEB

LOOKING FOR PARTICULAR KEYWORDS

AND SO IF YOU'RE LOOKING FOR

SOMETHING THAT SAYS PIZZA IT'S

GOING TO GO AND FIND THE WORD

PIZZA AS MANY PLACES AS IT CAN

FIND AND IT'LL CRAWL THROUGH ALL

THE DIFFERENT WEBSITES AND GRAB

THE ONES THAT SAY, HAVE THE

WORDS PIZZA ON THEM AND DISPLAY

THEM IN A LIST FOR YOU TO CHOOSE

FROM.

CLAIRE: HI MY NAME IS CLAIRE AND

MY QUESTION IS HOW DO COMPUTERS

PROCESS WHAT YOU TELL THEM TO

DO?

ANDERSEN: SO WHEN YOU TYPE INTO

A KEYBOARD AND YOU REQUEST THE

COMPUTER TO DO SOMETHING THAT

INFORMATION IS SENT TO THE

PROGRAM THAT'S ON TOP OF THE

SCREEN THAT YOU'RE LOOKING AT

AND THAT PROGRAM, BASED ON WHAT

THE PROGRAMMER HAS PROGRAMMED IT

TO DO IS GOING TO TAKE THAT

INFORMATION AND PROCESS IT AND

RETURN AN ANSWER TO YOU.

DIMITRI: HI MY NAME IS DIMITRI

AND MY QUESTION IS HOW DO THE

KEYBOARD BUTTONS PROJECT ONTO

THE SCREEN?

ERBEN: SO THE KEYBOARD BUTTONS

DON'T ACTUALLY PROJECT ONTO THE

SCREEN, YOU PRESS A CIRCUIT AND

THAT CIRCUIT INFORMATION GOES

THROUGH THE COMPUTER AND THE

COMPUTER PROCESSES THAT AND

IDENTIFIES WHICH KEY IT IS AND

THEY, IT HAS INSTRUCTIONS TO

DISPLAY THAT YOU TYPED THIS

PARTICULAR KEY AND THAT'S TURNS

ON AND OFF THE PIXELS THAT

REPRESENT THAT KEY.

OSCAR: HI MY NAME IS OSCAR, HOW

DOES THE COMPUTER KNOW WHICH

IMAGE TO USE?

ANDERSEN: THAT'S DONE BY THE

COMPUTER PROGRAM THAT YOU'RE

RUNNING.

SO IF YOU'RE RUNNING A COMPUTER

PROGRAM AND IT NEEDS TO DISPLAY

AN IMAGE THE COMPUTER PROGRAM IS

GOING TO SEND THAT IMAGE TO YOUR

VIDEO CARD AND THEN VIDEO CARD

WILL SEND THAT IMAGE TO THE

MONITOR AND THE MONITOR DISPLAYS

THAT IMAGE TO YOU.

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CARTAN-HANSEN: I'M SORRY

WE'VE RUN OUT OF TIME.

MY THANKS TO TIM AND FLOSSIE FOR

ANSWERING STUDENTS QUESTIONS.

ANDERSEN: THANK YOU IT'S BEEN

GREAT.

ERBEN: WE WERE HAPPY TO DO IT.

CARTAN-HANSEN: AND MY THANKS TO

THE FOLKS HERE AT HP FOR HOSTING

US.

IF YOU WANT TO LEARN MORE CHECK

OUT THE COMPUTER AREA ON THE

SCIENCE TREK WEBSITE-YOU'LL FIND

FACTS, LINKS, GAMES, OUR

COMPUTER BROADCAST SHOW AND LOTS

MORE.

AND EVERY WEEK CHECK OUT MY BLOG

FOR THE LATEST SCIENCE NEWS FOR

KIDS.

ALL AT IDAHOPTV.ORG.

THANKS FOR JOINING US FOR

SCIENCE TREK-THE WEB SHOW.

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