DISCOVERING COMPUTERS

[Music] what's happening what's going on where are you rushing to these students are rushing to learn about the exciting world of computers computers are in use all around us doctors can tell how well our bodies work by watching computerized scans this heart scan shows the heart beating and pumping blood this is a computerized picture the computers on Voyager 2 send photographs back to earth for scientific study [Music] scientists at Jet Propulsion lab used computers to control and track the spacecraft traveling in deep space this beautiful computer artwork was created by well-known computer artist John Whitney [Music] computers are used almost everywhere [Music] many people think computers are a new invention like these at NASA control what they are wrong computers have been around for a long time Cave people computed on their fingers and on their toes when they ran out of fingers and toes and had to count past 20 they started moving around sticks and stones our first known computers 2,000 years ago the abacus a simple calculator using rows of beads was invented in Asia and is still used today in the 1600s a frenchman named pascal invented a gear-driven adding machine 200 years later Babbage and Englishman designed a device that could add store numbers and give answers unfortunately at that time the machine was too difficult for them to build in the late 1800s an American named Hollerith developed a punched card that could store information it was used in the 1890 census row computers used in classrooms - these little pocket computers and getting even smaller wouldn't it be nice if a machine could help us with our schoolwork well it can computers are very friendly tell the computer what to do and it can do it faster than we can make fewer errors remember it much better and never get tired or complain imagine us working as fast as a computer without tiring [Music] hardware is the name given to the parts of the computer you can actually touch when you turn it on not much happens on the TV screen or monitor nothing happens because the computer is just a dumb machine it needs the intelligence of a person to give it instructions getting the instructions from the outside of the machine to the inside where they can be processed is called input one way this can be done is by typing on a typewriter like keyboard another way is by using a computer program already prepared for us programs are instructions to the computer that can be recorded on floppy disks or cassettes these programs are called software now we load the program from the cassette or disk into the computer by using the cassette player or disk drive this simple animation shows how the instructions call a computer program come from the outside to the inside of the computer to be processed now let's see what goes on inside the computer the inside is called the central processing unit or simply CPU the CPU is made up of three parts the control unit that keeps track of where everything is memory made up of a program area and an information area is where everything is stored and the arithmetic logic unit that does all the mathematic calculations or compares one bit of information with another let's see how the computer solves this problem 5+5 the first thing the control unit does is take the program from input and move it into the program area of memory then the control unit reads the instructions in the program area one at a time and does what the instructions tell it to do instruction go to input get a number move it into information area of memory instruction go to information area move the number into a rhythmatic logic unit then add same number to it instruction go to a rhythmatic logic unit take the answer move it into information area of memory instruction go to information area move answer to the output device of your choice when the answer appears on the TV screen it is called output and much of what goes on inside the computer is done on a tiny chip such as this one so now that a program has been loaded into the computer and you know how it works you become its master because the computer needs you to operate it as long as you continue giving the computer input you will be able to work together like two friends [Music] so what is a computer and how does it work it's a machine that takes in information called input processes it and gives back an answer called output [Music] you do not have to know how to write computer programs to use the machine the computer is very simple to operate just load an already prepared program into the computer and enjoy the adventures of learning now let's look at some short examples of programs where you can learn by inputting a response and having fun at the same time a math problem you input or type in the answer a typing lesson you type what appears on the TV screen many computers let you input a musical scale here's an English grammar lesson geography science grass chemistry art and these art programs written by students [Music] in many programs the computer will tell you if your answers are right or wrong if you're wrong the computer will wait for you to give the correct answer and sometimes if you still are stuck it may even help you solve the problem at the end of some programs the computer will give you your score how many answers you got correct and how many you got wrong this will be a big help to you and your teacher your teacher will have the scores immediately and will be able to know which students will need a little more help and which ones will be able to move on at a faster speed so what can a computer do and what can it not do we now know the computer is not just a toy it can be used as a learning tool a learning tool that improves the quality of education the computer cannot take the place of your teacher but your teacher can now have more time to help individual students unlike the science fiction stories the computer cannot take over the world it needs us to tell it what to do a computer is just a dumb machine if instructed incorrectly it will answer incorrectly computers can solve problems in a logical manner computers can work without getting tired computers can accomplish many tasks very fast and the computer's memory can last for a very long time I wonder if we instruct the computer to remember all the information seen in this film will it ok computer run it back [Music] [Music] the end [Music]