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chapter 1 computer hardware and vocabulary · 1 bit 8 bit 16 bit · 24 bit color 9 14 · analog 9 · ascii 5 · base two 4 · baud rate 11 · binary code 4 · bit 3 · bluetooth 15 · byte 2 · cd rom 11 · codec 16 · cpu 1 · crt 7 · daisy chain 15 · digital 10 14 · disk drive 6 · dos 7 · dot matrix 8 · dvd 11 · firewire 15 · floppy disk 6 · gigabyte 3 · gray scale 15 · hard disk 7 · hexadecimal 5 · html 16 · inkjet printer 9 · interface 2 · k or kilobyte 3 · laser printer · megabyte 3 · midi 10 · modem 9 · monitor 8 · motherboard 2 · mp3 files 13 · network 14 · nybble 5 · ocr 15 · parallel 9 · photo cd 15 · pixel 8,9,14 · printers 9 · public domain 13 · ram 1 rom 2 · scanners 13 · scsi interface 2 · sectors,tracks 6 · serial 9 · shareware 12,13 · star network 14 · tcp 9 · terabyte 3 · usb flash drive 15 · video board 2 · viruses 11 · video conference 15 · zip drives 7 cpu the cpu is the central processing unit it resides on one or more chips inside the computer each chip is a grid of silicon wires encased in a plastic container about the size of a fingernail although there are other chips involved and this is an oversimplification it works well to think of the cpu as the central component of your system it functions the way your brain functions coordinating the activities of the other devices although computers with vacuum tubes go back to 1946 the first microprocessor i.e computer on a chip was invented by ted hoff from intel corp in 1971 another important chip the ram chip is always blank when the electricity is off when you start up a computer and begin to work the information you type as well as the program that is in process all fit inside of ram when people refer to a 1.8 gig or 2 gig computer they are referring to the size of the ram capacity ram stands for random access memory a typical mac or windows computer now comes with two gigabyte of ram older macs and pcs in the early 1990s came with 1 meg of ram in the mid 1980s typical computers had about 1/8 of a meg of ram 128k and very primitive graphics the first microcomputer in 1975 altair had under 1k of ram which is about 1/1,000th of a meg gordon moore former ceo of intel and mentor of andrew grove time magazine man of the year 12/97 gets credit for what is now called moore s law chip power doubling roughly every 2 years and costs falling by 50 rom chips are crucial to the computer but not very interesting to us as consumers a rom chip typically contains frozen information fairly technical esoteric stuff that the manufacturer wants accessible at all times basic however was built into rom on the apple ii so that if you turned on that cpu without a disk drive you could actually start programming rom stands for read only memory rom chips are found not only chapter 1 · vocabulary · page 1

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in computers many appliances and even toys contain rom chips in fact the singing bass big mouth billie contains a rom chip in order for the cpu and other chips to talk to other devices an interface board is used to connect the electronics of one machine to another the board contains a printed circuit with a few special purpose chips the innovation of the mac plus back in 1987 was that it had a scsi interface builtin allowing for easy connection to hard disk drives the technology rivalry between the east coast rt 128 beltway and west coast silicon valley area was symbolized by the pronunciation of the word scsi east coasters wanted to pronounce it as sexy while west coasters wanted scuzzy as the lakers proved more often in the 1980s the west won and scuzzy became the accepted pronunciation by the way scsi which stands for small computer system interface is increasingly another obsolete word since usb firewire and bluetooth are taking over as faster ways for data to travel one special interface board the video board connects the computer to the screen it frequently has multicolored wires emerging from it typically rgb for red green and blue although most of us mixed the primary colors red yellow and blue to make other paint colors it turns out that the primary colors for electron beams are red green and blue another important board the motherboard is the main circuit board that all the ram chips rom chips and other interface boards plug into both the computer chip and the disk drive store information that is coded electronically the basic unit of information is the byte which is equivalent to one character or one keystroke for example the word hello is a 5 byte word because spaces are just as significant as letters new york is one 8 byte word which is the way most new yorkers say it anyway in fact it is very useful in teaching or learning word processing to realize that space bar and return each constitutes 1 byte you might say that the computer alphabet has 29 letters a-z space bar tab and return use the show invisibles command in your word processor to see all of these 29 letters chapter 1 · vocabulary · page 2

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1000 bytes 1 k how many bytes on a piece of paper well a good approach is to consider double-spaced text with wide margins for example you might have 50 characters across the page with a total of 20 lines down therefore we have 20 x 50 bytes or 1000 bytes on the page computer people refer to 1000 bytes as 1 kilobyte and then abbreviate it as 1 k just as 1000 bytes equals 1 kilobyte 1k 1 million bytes 1000k is 1 megabyte usually pronounced meg and 1 billion bytes 1000 megabytes is 1 gigabyte hard disks range from 40 meg to 80 gigabytes cds hold up to 650,000k which we call 650 meg or over 1/2 a gigabyte in spring of 1998 bill gates launched the terraserver project a database of satellite pictures terraserver.com of the world the web server contains over 1 terabyte of the terra stored in a database of 173.6 million rows one terabyte contains 1,000 gigabytes about 1500 cds or about 1 million floppy disks this chart summarizes basic computer literacy for various disks · double density floppy disk · high density floppy disk · typical hard disk drive · cd rom disk 800k 1,400k 80,000,000k 650,000k 800,000 bytes 1,400,000 bytes 80,000,000,000 bytes 650,000,000 .8 meg 1.4 meg 80,000 meg 650 meg 80 gig .5 gig how is each byte coded although this topic is not particularly useful many people find it interesting the inside of a chip looks like a grid of horizontal and vertical wires a junction point on a the grid is magnetized to be either on or off consider a 1 inch chip that has 100 horizontal wires and 100 vertical wires it looks like a gigantic tic-tac-toe board with 10,000 different junction spots or intersection points imagine that each one can be turned on or off with magnetism behaving like a light bulb let us call each junction of wires a bit and let us think of grouping the thousands of bits into groups of 8 using groups of 8 bits at a time we have a picture that looks like this it turns out that we can design a code of ons and offs so that each group of 8 bits holds one letter or symbol of the english alphabet how well first let s figure out how many different patterns of on and off we would find with 8 bits lined up if we had just a 2 bit computer we might have 4 different patterns for the 2 spots on-on · · on-off off-on off-off · o o · o o -· -· -· -· -· -· -· -· if we had just a 3 bit computer we might have 8 different patterns for the 3 spots on-on-on · · · off-off-on o o · on-on-off on-off-on on-off-off · · o · o · · o o off-off-off off-on-on off-on-off oooo · · o · o chapter 1 · vocabulary · page 3

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using the symbols 1 for on and 0 for off simplifies the explanation a 2-bit computer has 4 patterns 00 01 10 11 a 3-bit computer has 8 patterns 000 001 010 011 100 101 110 111 a 4-bit computer has 16 patterns 0000 0001 0010 0011 0100 0101 0110 0111 0001 1001 1010 1011 1100 1101 1110 1111 this system of 1 s and o s is really the base two or binary number system in math the word bit is an acronym of the phrase binary digit here are the numbers from 1 to 14 written in base two 0001 1 1000 8 0010 2 1001 9 0011 3 1010 10 0100 4 1011 11 0101 5 1100 12 0110 6 1101 13 0111 7 1110 14 here is larry bird s uniform number 33 written as a base two number 100001 each position stands for a power of two instead of a power of ten now let s figure out how many patterns in an 8 bit computer since a 2 bit computer has 4 patterns and a 3 bit computer has 8 patterns can you see that the number of patterns doubles as we add a bit can you figure out a good rationale for why it is so take the 8 patterns for a 3 bit computer put a zero in front of each pattern or put a one in front of each pattern you get the 16 patterns that for a 4 bit computer the end result is that an 8 bit computer has 256 patterns each one is equal to one letter of the alphabet a symbol on the keyboard or perhaps even a graphics character some of the 256 patterns may even be left unused this provides another way to understand a byte a byte is made up of 8 bits and is a coded way of representing one letter of the alphabet chapter 1 · vocabulary · page 4

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example #1 let us change 89 from decimal to binary the typical strategy is to write down 8 places labeling them from 1 on the right to 128 on the left we now distribute the 89 as if we playing the role of the banker in monopoly and have to pay $89 but can use only $128 bills $64 bills $32 bills etc and just one of each we first put a 1 in the 64 s place which leaves 89-64 or 25 left to distribute we next put a 1 in the 16 s place leaving 9 dollars and so on we get an answer of 01011001 example #2 change 01000101 from binary to decimal we begin with our 8 positions and now translate our 01000101 number into 1 in the 64 place plus 1 in the 4 place plus 1 in the 1 s place i.e with our monopoly money analogy $64 $4 $1 we get an answer of 69 example #3 interpret the months and date on this wedding ring on the right the 110 represents 6 june since there are 1 s in the 2 s place and the 4 s place the 100 represents 4 since there is a 1 in the 4 s place and 0 s in the 1 s place and the 2 s place we get an answer of june 4th example #4 consider the 3 byte word yes which is what most boston celtics fans said when rick pitino quit his job as the coach this word is made of 3 bytes or 24 bits or 6 nybbles yes the word nybble is legitimate though esoteric and means 4 bits or half of a byte and so rick can teach his children that 8 bits make a byte 4 bits make a nybble and 2 nybbles make a byte when you type the word yes on your computer each letter is translated into its 8 bit code each ascii code is 1 byte made up of 8 bits y code 89 01011001 off on off on on off off on o·o··oo· e code 69 01000101 off on off off off on off on o·ooo·o· s code 83 01010011 off on off on off off on on o·o·oo·· the computer is therefore storing 3 bytes of information to remember the word yes since each byte is made of 8 bits the computer is storing the 3 bytes as a series of 24 bits if we are looking at a disk we would be referring to 24 spots of magnetism on one of the circular tracks of the record inside a chip we would be referring to 24 intersections of wires on the grid as mentioned above the most common coding system for relating binary numbers to english symbols is called the ascii system it means that a is code 65 b is code 66 and so on through z which is code 90 ascii stands for american standard coding information interchange pronounced ass-key and it proves that the computer industry is not completely idiosyncratic chapter 1 · vocabulary · page 5

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and eccentric now that you know that a is code 65 look back at the word yes and see if the three ascii codes 89 69 83 make sense another computer system for coding numbers is called hexadecimal or base 16 in this system we use one symbol for each number from 1 to 15 we use a for 10 b for 11 c for 12 d for 13 e for 14 and f for 15 in the hexadecimal system after the one s place we have the 16 s place so the number a3 means 3 in the ones place and a or 10 in the 16 s place i.e a3 10x16 3 163 let s compare the 3 number systems decimal called base 10 10 symbols used 0 to 9 100,10 1 s place binary called base 2 2 symbols used 0 1 4,2 1 s place hexadecimal called base 16 16 symbols used 0-9 and a,b,c,d,e,f 256,16 1 s place below are the ascii codes for the common 26 uppercase letters of the alphabet a to z together with their binary and hexadecimal equivalents on the old imagewriter printer if you turned on the machine incorrectly you got a series of 2-character hexadecimal codes if the printout was 4c 41 52 52 59 20 42 49 52 44 20 47 4f 20 44 41 4c 4c 41 53 0d you can decipher using this chart what was really typed 20=space bar and 0d=return · thanks to theresa overall from lamplighter school dallas tx for fixing this coded message · ascii binary letter code equivalent a 65 01000001 b 66 01000010 c 67 01000011 d 68 01000100 e 69 01000101 f 70 01000110 g 71 01000111 h 72 01001000 i 73 01001001 j 74 01001010 k 75 01001011 l 76 01001100 m 77 01001101 hexadecimal equivalent 41 42 43 44 45 46 47 48 49 4a 4b 4c 4d ascii binary letter code equivalent n 78 01001110 o 79 01001111 p 80 01010000 q 81 01010001 r 82 01010010 s 83 01010011 t 84 01010100 u 85 01010101 v 86 01010110 w 87 01010111 x 88 01011000 y 89 01011001 z 90 01011010 hexadecimal equivalent 4e 4f 50 51 52 53 54 55 56 57 58 59 5a example #5 let us make sense of the use of hexadecimal numbers in the html command

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exercises change 133 and 233 from decimal to binary and hexadecimal change bird into a series of ascii numbers a series of binary codes and a series of hexadecimal codes floppy disk disk drive each floppy disk was actually a circular record encased in a square shell divided into concentric circles called tracks each track is divided into chunks of information called sectors in the mid-1980s the most common size disk was the 5.25 floppy which truly flopped apple ii computers held 140k pc computers held 360k or 1200k in the late-1980s the 3.5 floppy became popular the original one hole regular density held 800k 800,000 bytes or 4/5 of a megabyte even though the casing is hard plastic these 3.5 floppy disks are not called hard disks the inside plastic circular record really does flop all 3.5 disks hold 1400k 1,400,000 bytes or 1.4 megabytes and have 2 square holes computers are now floppyless and the floppy disk drive is a trivia question the new song at disneyworld is it s a diskless diskless world they make really nice coasters hard disks it is best to think of a hard disk drive as a circular piece of metal that has been sealed in a dust free environment you do not remove a hard disk you do not handle it you can save or load onto the hard disk and move programs and files from your floppy drive to and from the hard disk we use the words hard disk and hard drive interchangeably because a hard disk is sealed in a special environment it can spin faster and store more information generally a hard drive consists of several metal platters separated by about 1/8th of an inch a typical external hard disk drive in 1987 held 80 megabytes and cost $1400 in contrast an external hard disk drive in 2011 that holds 1 terabyte costs $70.00 zip disks and superdisk the external zip drives by iomega.com attached to a mac or pc and stored from 100-750 megabytes on what some consumers think of as a thick floppy the disk itself is portable durable and just a bit bigger than a standard 3.5 floppy this technology like so many others went the way of the horse and buggy flash drives lightweight external disk drives and online storage-all are moving zip drives to a state of extinction dos this ancient acronym stands for disk operating system and it refers to the storage system for the particular disk the old apple iii computer had the sophisticated operating system owners referring to loading up the apple sos sauce when macs users refer to system 9.0 or x they are referring to the dos of their mac if you are over age 30 try to think of dos as analogous to records playing at 33 45 or 78 rpm if you are under age 30 think of cds vs dvds when you turn on a computer the first thing that happens is that dos is loaded from the hard drive into a portion of the ram chip someone once remarked that dos is like the morning coffee of a computer crt the crt is the screen the monitor the letters stand for cathode ray tube which is what old televisions used to be called crts have varying resolutions usually described as a rectangle of pixels each pixel is one dot on the screen most computers use a resolution of 72 dots per inch chapter 1 · vocabulary · page 7

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analog vs digital is a fundamental conceptual distinction that used to be reserved for technical whizzes and now finds its way increasingly into everyday conversations when a device functions analog such as a standard clock with hands the mechanism proceeds through every possible variation from one extreme to the other if both hands are at the 12 it is midnight but as the next few minutes pass the big hand sweeps through every continuous position on its way to being 5 past midnight analog devices are like continuous functions in math other examples would include a rotary dial on a radio that finds every frequency from 580 to 1490 as it is turned a mercury thermometer or an oven rotary dial in which you estimate 375 degrees on the other hand digital means that the variations have been converted into discrete numbers with a definite step from one to the next digital devices are not just watches musical compact disks contain magnetic 1 s and 0 s in the grooves so that the music is in effect coded and digitized old-fashioned lp records vcr tapes and audio tapes are analog while cds and dvds are digital modems the modem allows your computer to communicate via the telephone with other systems the acronym modem stands for modulator demodulator since it modulates analog into digital and visa versa baud rate means the rate at which the data travels on the phone line baud means bits per second so a baud rate of 14,400 baud usually pronounced 14.4 means 14,400 bits per second i.e 1,800 bytes this is two pages of text double-spaced per second originally modems were between 300 and 2400 baud and cost over $300 every computer on the web has an ip address either fixed or randomly assigned ip stands for internet protocol a typical ip address is a series of numbers e.g 207.31.250.18 which can then be turned in to a name e.g gatornet.chapin.edu fixed ip numbers used to be common but are increasingly hot commodities with most isps businesses and schools serving up what are called random ips using a dhcp server dhcp stands for dynamic host configuration protocol two commands built into the run feature of pcs illustrate what ip numbers are all about by typing ping xxx or tracert yyy with xxx or yyy being a specific ip number you will find out how many milliseconds millionths of a second it takes to send a signal to that computer and back don t forget that electricity travels around the equator of the earth in 1/7th of a second chapter 1 · vocabulary · page 8

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it is a mind boggling reality of the internet and the web that all the data travels in packets from one computer to another frequently stopping at many places in between midi stands for musical instrument digital interface a midi connector plugs into your computer typically from an electronic keyboard some keyboards are midi compatible though cheap ones are not once you have connected your music keyboard to your computer you can enter notes on the screen via the piano keyboard the minimum cost used to be about $300$400 for the midi-compatible piano keyboard and $75 for the midi-interface external cable which connects from the computer s modem port to that keyboard then you need music software that has midi features garageband for the mac works well with external keyboards etc a cd rom holds up to 700 megabytes over 1/2 a gigabyte the equivalent of about 465 high density 1.4 meg floppy disks in basketball terms this represents a stack of typewriter pages the height of the fleet center initially computer cds were read-only you did not record onto them but only get information from them however all computers now give you the ability to save onto chapter 1 · vocabulary · page 9

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burn onto cds because these computers now come standard with cd-rw which can both read and write cds voice digitizers allow you to record voices and sounds and do something like word processing on the recorded sound by turning the sounds into 1 s and 0 s once the sound is turned into a wave form on your screen the software allows special effects such as reversing the sound amplifying it making it reverb as if it from outer space or a concert hall audacity free software available to download is a powerful sound editor available for both macs and pcs garageband a mac only product also provides voice digitizing and editing capabilities dvd stands for digital versatile disk and gives us a chance to use 4.7 gigabytes and 17 gigabytes in our everyday vocabulary dvd discs make cds look like the 5 1/4 floppy disks of earlier times just the single sided single layer dvd disc itself offers 4.7 gb of capacity which is worlds away from a cd s 680 mb capacity when we start discussing the 17.0 gb capacity of the double sided dual layer dvd it s like comparing the scribbles of a one-year old toddler to a monet masterpiece 1 a recordable dvd can contain 5 gig of data equal to 3,472 floppies many pcs and macs but not all come standard with a dvd burner encountering computer viruses is now common to many of us to simplify one might say that a computer virus is comparable to a special device inserted into the carburetor of a car by a dishonest mechanic even worse would be if the car mechanic wired your car so that whenever you park next to another car the problem in your car jumps and spreads to the next car in other words computer viruses can jump from disk to disk spread via internet downloads or even worse now via macros in microsoft documents and e-mails who creates these things sometimes teenagers and sometimes adults a computer virus can be defined as a computer program that does something strange to your files and disks and spreads to other computers via e-mail networking and floppies daily e-mails warn of new viruses and now reports of the disasters incurred by viruses spreading throughout networks appear regularly on the six o clock news one article used the metaphor of cowboy culture of hacking to describe this phenomenon for under $100 you can buy a reliable relatively easy virus program e.g sam norton mcafee antivirus that will disinfect existing hard disk drives and prevent subsequent viruses from coming back public domain programs are available to download at sites like download.com and commercial programs are available freeware or open source software can be copied and distributed freely this is in contrast to commercial software which is copyrighted and for which 1 rich d ambrise engineering manager maxell corp www.cd-info.com/cdic/technology/dvd/dvd.html chapter 1 · vocabulary · page 10

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it is illegal and dishonest to distribute shareware software can be distributed but users are honor bound to pay for it or delete it after a short period of trial usage trying to understand the size of computer graphic files becomes an excellent exercise in synthesizing the concepts of bits bytes kilobytes megabytes and pixels we begin by the fact that the screen resolution is generally 72 pixels per inch and so a one inch square would contain about 5,184 pixels 72x72 · if you are working in one-bit color then each pixel can be only black or white so it occupies one bit either 1 or 0 therefore 5,184 pixels would occupy 648 bytes 5,184/8 which is under 1k · if in 8-bit color then each pixel can be one of 256 shades of gray or 256 colors the number 256 is 2^8th power this means that 5,184 pixels would occupy 5,184 bytes or approximately 5k · if in 16-bit color then each pixel can be one of 65,536 colors 2^16th or 256 x 256 thus 5,184 pixels would occupy 10,368 bytes each pixel needing 2 bytes to store 1 color choice out of 65,536 · if in 24-bit color then each pixel can be one of 16,777,216 colors the number 16,777,216 is 2^24th power this means that 5,184 pixels would occupy 15,552 bytes since each pixel would require 3 bytes to store its color choice out of 16,777,216 possibilities by the way the best way to picture 16.7 million colors is to think of mixing 256 shades of each primary color to test this out we created a one inch square using photoshop it took 7,528 bytes to store the 8 bit color version 14,027 bytes for the 16 bit color version and 3,125 bytes for the 1 bit version since other info is stored by photoshop this tends to validates the above theoretical discussion here is the summary extended to a 2 and 3 inch squares remember that when you double the length and width of a garden you multiply its area by 4 picture size one bit color 8 bit 16 bit 24 bit 1 inch square 2/3 of a k 5k 10k 15k 2 inch square 2.7 k 20k 40k 60k 3 inch square 8k 45k 90k 135k and so that 3 square 24 bit color picture would consume about 10 of a high density disk and this is all at 72 pixels per inch which is the screen size and a low resolution for anyone doing serious graphic art if we work at 150 pixels per inch then each number is quadrupled if we choose to work at 300 pixels per inch then that 3 square picture at 24 bit color consumes almost an entire high density disk understanding digital sound one second of stereo 176k2 with the solid base of bits and bytes we are now able to understand how sound is stored digitally e.g cd or computer a sampling rate of 44,100 means that the sound waves are inspected that chapter 1 · vocabulary · page 11

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many times each second to determine its qualities note tone and amplitude there are 65,536 choices for each specific sampled sound since 65,536 256 x 256 and each byte has 256 patterns this means that each sampled sound consumes 2 bytes of data thus 44,100 samples in one second would be 88,200 bytes or 88k this now gets replicated for both the left and right channels stereo yielding 176k therefore one minute of data would be 60 x 176k or 10,560k i.e 10 megabytes 65 minutes would therefore equal 650 megabytes filling up a typical musical cd to make a connection between digitizing art and music the above chart shows that a 3 inch square graphic at 8 bit color contains about the same number of binary codes as 1 second of stereo sound understanding mp3 files and mp3 players typical sound files are recorded as aiff files with a song that lasts for 3 minutes requiring about 33 megabytes of storage space the mp3 file format compresses that file to about 1/10th of its size in the same way that jpeg and gif provide compressed versions of graphics so each mp3 file is about 3 meg with virtually no difference in quality these smaller files can be more easily downloaded moved via cable into a portable mp3 player or stored on a hard drive mp3 comes from the word mpeg which stands for moving pictures expert group mp3 is short for mpeg audio layer 3 the compression algorithm a computer network is physically cabling the various computers let s call them a,b,c,d and e together on a network you can share files printers cd-rom drives and most importantly the connection to the web and the outside world a scanner digitizes a graphic into 1 s and 0 s to be stored in the ram chip and subsequently onto the disk drive the larry bird graphic with 00100001 on his uniform involved each pixel being either black or white 1 bit color and was poor quality like most of the pictures in this book gray scale means that each pixel can be one of 256 shades of gray e.g the larry bird graphic at the end of this chapter 8 bit color means that each pixel is 1 of 256 colors 16 bit color means that each pixel is 1 of 65,536 colors 24 bit color means that each pixel is 1 of 16,777,216 colors ocr software an enhancement to the traditional scanner digitizes a printed page of text into an editable word processed document digital cameras store pictures or movies on memory cards or directly onto a cd or mini-dvd a lower quality picture is taken at a resolution of 640 x 480 or 307,200 pixels and 1024 x 768 or 786,432 pixels note that these images are under 1 million pixels which is called a megapixel in contrast better digital cameras have a resolution that is at least eight times greater their resolution is a standard quality 2048 x 1536 or 3145728 pixels or what is called 3.3 megapixels or more these images are stored on a smartmedia card basically a ram chip on a card the size of a thick credit card sold in sizes up to 2 gig or even more these memory cards can then be inserted into a printer or a transfer device to move the files to a computer via usb or firewire or to print directly from a photo capable printer most camera shops and services will transfer pictures onto cds each photo cd up to 650 meg holds about 80-100 images stored in multiple formats including 24 bit color or you can send your film to an online service that will both process your photos and post your photos online or print huge reproductions you can then download these images for use in word processing slide presentation or social networking sites one caveat although you will want to take photos at the highest quality be aware of the desired chapter 1 · vocabulary · page 12

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output for instance if you are planning on using the photos for a website or a powerpoint presentation resist the temptation to take the pictures at 8 megapixels you will be creating unnecessarily large and cumbersome files guaranteed to create gargantuan powerpoints that you will be unable to e-mail similarly if you want to e-mail photos to friends and family take the photos at a low resolution or re-image using photo editing software so that they will be able to receive and view your photos have you ever received a file so big that you could not see the entire image on your computer screen the culprit the too-large resolution if you are planning to print your photos at 11 x17 or larger then you should use the best resolution but for most print jobs you can take pictures at less than the highest pixel rate flip video cameras and other low-cost digital video cameras are incredibly popular fueled by youtube and other social networking sites the beauty of these cameras is their ease-of-use easy syncing to upload to youtube their size and their durable construction sadly the flip camera has been discontinued but other inexpensive cameras can take its place usb stands for universal serial bus and all computers come with one or more usb connectors that let you attach everything from mice to printers to your computer quickly and easily usb was designed to end the headaches of attaching peripherals and worrying about cards serial ports parallel ports and card slots connecting a usb device is simple find the usb connector on your computer and plug the usb connector into it usb devices are hot-swappable which is a fancy tech way of saying you can plug or unplug them with the power on usb devices include scanners mice digital cameras modems zip drives most computers have 2 or more usb ports but you can also purchase a usb hub for multiple devices the usb flash drive about the size of a keychain plugs into a usb port allowing you to move and copy data back and forth between the flash drive and the hard drive these tiny usb devices also called memory sticks or thumb drives can hold up to 256 gig of data or more including images audio files and video files many companies now produce flash drives in all shapes and sizes including actual sticks pens and even stylish mother of pearl necklaces firewire is a high performance serial bus for connecting devices to your computer firewire provides a single plug-and-socket connection that allows you to attach up to 63 devices with data transfer speed up to 400 megabits per second this high speed of data transfer is particularly good for multimedia applications with a computer equipped with firewire any device for example a video camera can be plugged in while the computer is running the official name for the interface is institute of electrical and electronics engineers 1394 high performance serial bus or ieee 1394 the usb port provides the same plug and play technology and it is less expensive but the chapter 1 · vocabulary · page 13

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data transfer of usb is 12 mbps million bits per second firewire provides the bandwidth necessary for audio imaging real time video and other streaming data firewire allows easy connection to digital audio devices digital vcrs digital video cameras and even digital hard disk drives with firewire the link between a dvc camcorder and the computer is direct so there is no need for a video capture board firewire is no longer supported by many laptops bluetooth is short-range wireless connections between desktop and laptop computers pdas cell phones printers digital cameras headsets keyboards and even a computer mouse bluetooth uses radio signals that can transmit even through walls so the bluetooth-enable devices to not have to be in the same room to communicate with each other how does it work one bluetooth device sends transmits a message looking for another bluetooth device to connect with similar to internet dating i suppose when the two devices determine that they can communicate they establish a connection each bluetooth device can simultaneously connect to up to seven devices basically bluetooth is wireless usb in the years to come more and more bluetooth products the apple tv ipods and other mp3 players will be produced for instance you can connect a bluetooth phone to the web and then connect to your bluetooth laptop you can be checking e-mail while traveling in your car if your computer is not bluetooth capable you can purchase a bluetooth adaptor or you can build a bluetooth transmitter to integrate your ipod into your home stereo system video conferencing while some schools have dedicated videoconferencing equipment more often than not schools are using skype skype.com facetime or websites dedicated to on-line conferencing with the ability to share desktops documents whiteboards and voice ipods are not always thought of as educational tools but the ability to turn them into digital voice recorders ensures their use in all classrooms many companies sell attachments that will turn even the newest ipods into digital voice recorders additionally the outpouring of podcasts including the wonderful educational podcasts available through itunes university increase the educational value of ipods even more the ipod is a portable music device that among other things play music files such as mp3 s the music is not saved in analog form instead it is saved in digital form in long streams of 0 s and 1 s ipod s also play aac wav aiff apple lossless and audible 2 3 and 4 formats youtube and other videos can be downloaded onto video ipods so they can be used to view tutorials and other educational films found throughout the web chapter 1 · vocabulary · page 14

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slingbox connects to your home or school network and then to a cable box dvd player and/or television to broadcast the video signal through the internet a computer equipped with slingplayer software a free download from sling,com and of course connected to the internet can then view television remotely how does it work the slingbox compresses the television signal and streams it through your home network you can then both watch and control your television from anywhere in the world the slingbox allows avid new england patriot fans who happen to live in new york to view patriots games from a slingbox residing in massachusetts the slingcatcher will display anything on your computer onto a television monitor digital document cameras display real-time images of any static or moving object placed under the camera lens you can show just about anything on a large screen by connecting the document camera to a projector the image projected can also be digitized or in the case of the camera created by smart technologies incorporated directly into a smartboard notebook presentation math teachers can easily display a problem-set from a textbook science teachers can quickly share a previously created hand-out or a 3d model of human anatomy a computer teacher can explain the inner workings of a hard drive chapter 1 · vocabulary · page 15

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