Hello everyone, welcome back to my channel. My name is Kumi Tassen. So today we're looking at input and output devices.
This is chapter two, the theory in the theory aspect of the Cambridge IDCSE ICT. So in this chapter, basically we'll look at input devices and output devices. So the main objectives we want to focus on here is to understand the characteristics of the of input devices their uses are advantages and disadvantages secondly we also look at a certain category of input devices which are direct data entry devices such as card readers ocrs and the rest look at their uses advantages and disadvantages and likewise we do the same for the output devices so let's get straight into it now the first thing that we hear is to look at input devices and their uses Now, simply, an input device is a hardware device.
It enables you to or allows you to enter data into a computer. This is like a simple input device like a keyboard. You enter data before the data is processed.
After the processing by the CPU, the data is sent out using an output device, which we'll be looking at later on in this presentation. or the data can also be processed and stored and later retrieved when needed. Now, moving on, we have two main categories of input devices, that's the manual input devices and the direct input devices. When we say manual input device, we are looking at input devices where much human effort is needed to enter data, such as the mouse, the keyboard and the others will be looking at subsequently. and then we have direct data entry devices when little human effort is needed things like barcode readers scanners and the rest so those are direct input devices direct data entry devices now let's begin with the manual input devices before we go to the direct data entry devices for manual input devices the first one is the keyboard this is the most common and basic input device any computer you go to it must have a keyboard you'll definitely find a keyboard so basically the keyboard can be also be wired wireless wired meaning you connect it with the usb cable via usb port or you can use a usb dongle to connect it while the keyboard can be you know usually from any direction and then on devices like tablets mobile phones and some laptops you have virtual keyboards meaning you have a touch screen through which you can access the keyboard In terms of advantages, what are the advantages of keyboard or the pros?
Now, they are easy to use for most people, fast text entry into documents, easy to verify data during entry. Disadvantages, slow data entry compared to direct data entry devices as we'll be seeing. Then we have device takes up text space, that's also a disadvantage, can be difficult to use. Now, the next form of manual input device is Numeric Key. parts so these are just a certain category of keyboards but mostly they contain just numbers like what you will find on uh atl's pos chip and pin devices so that is uh those are numeric key part so the you mainly find that being used for spreadsheets uh data entry maybe you have a spreadsheet where you need to enter a lot of numbers so you find things like this now what are some advantages of this category of keyboard they are faster than keyboards for numeric data entry obviously you just want to type number so they will definitely be faster than using a keyboard now very portable compared to standard keyboards they are smaller in size so very often they'll be portable what are some disadvantages they might be difficult to use in case of small keys yes because of their small size the keys will definitely be small or something i find that difficult to use and then there's also difficulty in the text especially on telephones like if you look at the older telephone they had keys like this and then beneath it you just see some a b c d e f and those things so to move from the number to the letter you have to do a certain you have to press quite a number of times so that is difficult now the next input manual input device is the mouse uh it's also very amount it's very common you just move around on the smooth surface to control your concept like what I'm doing now I'm moving my mouse on a smooth surface a mouse can also be wired to wireless so you can have a mouse with a cable like this connected to your computer or it doesn't have a cable at all you just use a dongle you plug to your computer and you can access it with a wireless technology Now, mouse or mice are basically used for opening, closing, minimizing software and others.
So basically, that's what we use them for. Now, what are the advantages of this mouse, of a mouse? Firstly, it's a fast method for selecting, opening or closing apps.
It can take up little deck space compared to the keyboard. Disadvantages, we have difficulty to use if surface is not flat, yes. And then we have easy to get damage. ball mouse is to get that dirt that's so the ball mouse for instance even there's an older style mouse of because he uses they easily grab that from the surface and when they don't that clocks on it it's uh difficult to use now the next input device we have is the touchpad this is uh like a mouse on the laptop so that's what the touchpad does is the main point device on laptops moving fingers on the surface and then tapping provide users as uh uses provided it as in the mouse above so you just move your fingers here you can scroll you can tap to click or you can use these buttons to click so basically it's a mouse but in a just in a different uh type of design it has the main functions are the same functions as a mouse so what are the advantages of a touchpad faster than keyboard yes no need for separate mouse and extra tech space because the mouse the touchpad is built directly on your laptop so it comes as a single unit so there is no need for extra space extra space disadvantages they are difficult to use by people with hand or risk problems if you have a hand or this problem you find it difficult to use the touchpad because you need to kind of at times you curve your fingers or those things that will cause you risks problem Now, they're difficult to use compared to the normal mouse.
That is true. Some people really find it difficult to use the touchpad compared to the mouse. That's why you see very common, even people with laptops who still have an external mouse, they walk around with.
So, yeah, that is true. Also, the next input device is the tracker ball. Actually, this is an ergonomic kind of mouse.
It's the same as the normal mouse, but the ball is on the top as you can see here. It's suitable for users with repeative strain injury or if you want to prevent such injuries, you can make use of this type of mouse. It is also using an industrial control to navigate processed screen. So you'll find this also in industrial controls.
What are some advantages of the tracker ball mouse? They are easier to use than the normal mouse, they are more robust and also more accurate in counting. Position the cursor on a particular place more accurately. Disadvantages, they are more costly than mouse.
Normally, additional functionality, it is easier than all those things. So definitely that comes at a cost. They may require training before use.
So that is also a disadvantage because you might not want to be trained or you might incur charges just to train to be trained to use the mouse. now the next manual input device is the remote control which i believe we are all familiar with you can use the remote control um basically it employs infrared technology so what you see here this green thing uh uh is there's a bob usually in front here which is the emitter and then the tv or whatever device you want to control has a receiver so whatever button you press on this uh remote here and it activates something when a receiver picks up that signal and maybe it's to switch off the TV like pressing the red button or it should switch to channel and all those things so you can use it to control televisions uh DVD OCD players you can also use to control robots and other machineries now an advantage or advantages of the robot countries easy to use they can be operated from a considerable distance disadvantages signals can easily be blocked yes might be difficult to use by some persons especially for advanced control that's true so it's a disadvantage now the next thing is the joystick so a manual input device you just hold here and you can move around just like maybe the tracker board or the other mouse now they are mainly used for gaming you can use it for flight control simulations so that's where things like this coming advantages easy screen navigation that keyboard so that's an advantage of the joystick a disadvantage it's more difficult to use compared to standard mouse so that's also a disadvantage now we move on to touchscreens which are also a manual input device the touchscreen you can uh is used to select or input options so you use when you tap you are sending information to your computer so it's an input uh we use touchscreen basically on atms pos mobile phones tablets interactive whiteboards probably laptops and many other areas so you'll find touch screens there so they they function as input devices and later on we also find out that touchscreens function both as input and output devices now what are some advantages of touch screen faster entry options than using the normal keyboard or mouse very easy method for choosing options and of they are also very user friendly and for disadvantages we have the user is limited to available input options such as on an atm machine you just you can only select the options that are available then the screen can get very dirty so where the touchscreen is used in public cases public for public use like ATMs accounts of variegated now the next manual input device while looking at these light pens basically they are used with computers at input device so the light pen is an input device where you write on the screen maybe you can mostly they use it with cathode ray screen to to select objects or they can use it for drawing you can also use to draw on screen so it's a light pen it's just like a stylus but it's just a it's just a very modern style of technology now what are the advantages of light pens uh they have greater accuracy than touch screens yes they very they are very handy in cases where space is an issue so you can i mean they're very small so instead of probably having a mouse you prefer to have these two maybe if you just want to be drawing for selecting things so they are also easy to use disadvantages you can have lagging problems to enter on screen and then currently light pencils of this nature are currently used just with the crt monitors so they are also an outdated technology so it is advantage the next input device manual input devices are scanners we use them to enter information from hard copy so you just can't whatever document photograph or whatever it may be you scan it from hard copy to text the advantage is scans information which can be stored in different formats yes and then you have faster information entry disadvantages we have limited quality depending on the result scanner yes so when they scan the tech the hard copy to text you find that the institution is not really good and then some that fairly slow in terms of when especially when the resolution is higher so it takes a lot of time to scan to make sure everything is set clear now the next manual input device we have is the digital camera basically right now our smartphones laptops and others most of them they come with digital camera so we use them basically to take photographs video recording and orders and then you could also find this use in cars for data capture or enjoy it while reversing And the advantages of digital cameras is they produce better quality images than the traditional cameras. They are also easier and faster to upload.
So you don't want something that you snap a picture and you take forever to send it wherever you want it to go to. Disadvantage is user often requires proper training before you solve a device. That's from sophisticated cameras and you definitely require to be trained before you can use it effectively.
So that's a disadvantage. loss of jobs by artists as most software are doing so now there are software that can do editing they can even help you take very good quality pictures so photographers are probably going out of you know that are losing their jobs artists and others because of those kind of things microphones now a microphone might not always look like this but at different versions the idea is when you speak yes you can send in speech which is an input you can send in speech sound voice recording also and your computer picks that up so it can be wired or wireless meaning you connect with the usb or some you can use a download to connect they can connect to connect them you can have my microphones we have microphones in our mobile phones right now i am using a microphone to record this presentation so On our mobile phones, when you're making a call, it's a microphone that is picking up your voice and maybe other technologies are involved to transmit your voice to whoever you're making the call with. so advantages they are faster they are faster text entry than typing with keyboard yes you can use speech to text meaning you speak and your microphone picks that up and then you see text on screen and then it aids in safety when using voice activation and security system yes some people there are security systems out there where they can they use uh mouse microphones or or sound things that pick up sound or movement and the signal is given out Now, disadvantage is sound files can use up a lot of space, yes, when you record with the microphone and all those things, they can take up a lot of space.
And the voice recognition is not as accurate as manual typing, that's true. When you're typing speech, your pronunciation has to really, really be good so that whatever you're saying is typed exactly the way it should. So, that is also a problem. Now, away from manual input devices, there is one major area of input devices.
which is a world sensors basically when we talk about sensors that input devices because the the measure sensors measure or continuously changing physical quantity so they measure things like temperature pressure humidity moisture which is the same thing um ph they can measure the maybe the oxygen content in water and all those things so that is where sensors come if you go to an automated system you'll find that you have sensor maybe to constantly check the temperature and send that information to a computer but now there is one thing we need to take note of sensors most sensors are analog in nature because they need to measure analog data so when this analog data is captured it must be converted to digital data because the computer only understands digital data as we saw in chapter one there was emphasis on this whenever you have analog data you must convert it to a digital form using an analog to digital converter so that the computer can understand whatever you're talking about so analog is continuously changing data while digital is just discrete like um it could be high low high or low high or low so one to zero that's what the computer understands and with the help of an analog to digital converter since the measurement from sensors can be converted to digital format for the computer to understand and take appropriate action. Now, these are different categories of sensors and these are their applications. Then we also have their some advantages and general disadvantages of this sensor. The first one is the temperature sensor. We can use it for temperature monitoring, automatic washing machines, central heating system, automated glass houses, ovens and many other areas.
we have the pressure sensor used to detect pressure changes in intruder alarm system robotics environmental monitoring we have the light sensor you could use it to detect lighting automatic glass houses automatic doors intruder alarm system street light control yes sound usage intruder lamp system monitoring liquid powder flowing pipes and many others humidity or moisture sensor we could use it in automatic glass houses environmental monitoring in factories where moisture levels are crucial For example, manufacturing of microchips, paint spraying. So those are places where you need to keep moisture levels at a certain required level. Now we have the pH sensor used to measure pH levels in chemical processes, environmental monitoring, automatic glass houses and many others. And now for advantages of these sensors, we have they are more accurate reading compared to human readings. you cannot ask a human to measure the temperature of something every two seconds throughout the day that won't happen it won't be effective but sensors can do that perfectly well they are more reliable especially as reading needs to be taken continuously yes as i just explained if you want a temperature to be taken every second or maybe every few seconds a sensor is the ideal thing a device to to use input device to use a human being cannot do that effectively then it's also more suitable for hazardous systems so they require little human intervention yeah if you look at all these spacecrafts or um that sent out into space you find out that they send back images you even get to know the temperature in like we know the temperature in mars how they are moisture content and all those things it would help of things like this the help of sensors so uh sensors are very very very important and you go to some places in really advanced countries and the rest you'll find that license of maybe that used to come through uh automatic street lights along the road uh i mean even in almost everywhere this is done I mean when it's getting dark lights just come on when it's getting when it's early in the morning lights automatically go off so that is where sensors are sensors this is how sensors can be used in our daily lives disadvantages the 40 sensors can give poor reading that's true most sensors are analog and often use an adc which is additional cost yes as we explained so this picture here simply this is a plant and this is a moisture sensor this is a microcontroller but an Arduino yeah this is an Arduino bot so what is happening here is this moisture sensor maybe you program this bot to make sure that maybe the moisture level here is always at a particular point once that moisture level is below the sensor will send that oh the moisture level below meaning the soil has become dry So you probably have to come and what I said this is what some people employ their farms On a large scale to you know, they don't need to be checking that is this plan trial or the stick So this was some people and you can even go for that to make the whole system So that you don't need to come on what I did what that is on its own So I mean their system existing like that and worked on a number of them.
So away from sensors let's look at a past example question in this area so they say a river authority is concerned about levels of pollution in a major river the quality of the water in the river needs to be monitored using sensors now there's a name three sensors that could be used to measure the pollution in the river yeah you could use an oxygen sensor that one maybe measure the oxygen levels in the river and you could use a light sensor the light sensor or baby check out how much light can pass through the water so that can also tell you how polluted the water is ph standard uh there are standards for the ph of water which may be good for drinking and others and then to be dizzy simply it measures how clear the water is so clarity you can so it is another type of sensor you can use so any of these three will give you your max so that is simply that is it about sensors Now, the next objective we have is to understand characteristics of direct data entry devices. This is also another broad category of input devices. So, with this one, little human effort is needed to enter data.
Now, the first direct data entry device we will look at is the magnetic stripe reader. Simply, erase data from magnetic stripe found on the back of the device. debit card so this is a debit card this black thing here is a magnetic stripe so what you do is you just swipe the card and it reads off that information so what is embedded what have i for the information stored on this magnetic stripe would be your account details login details and maybe to your account and others and then it is commonly you find this magnetic flyer redirection electronic phone transfer or yeah at point of sale terminus you could also find it in a security buildings and arrest that some buildings or hotel rooms you have to you just swipe a card to get a get access to your room and uh for advantages the magnetic stripe reader has fast data entry compared to using keyboard or keypad error free no typing you don't need to type secure form of data entry it's also a very robust device disadvantages you can damage on magnetic stripe can damage on the magnetic stripe this black area here yeah i could lead to data loss uh needs close out contact to work so you need to swipe it it's not something that you can use wirelessly strong magnetic fields can lead to data corruption numbers that is true now the next direct data entry device you want to look is look at is the contact that's david card readers so this is one uh the the contactless debit card reader raise data of a chip that emits radio is this chip is found on what the debit card so there's a chip here you see when you have a cd sign means radio like it's a wireless kind of technology so once you re you maybe you do a purchase from a shop or online no from a shop it has to be a physical what you just do is you maybe the key in the amount you put your card over it and then it's picks up the signal and that amount is deducted from your card advantages fast transactions within seconds data is protected so with 128 bit encryption and then we have error free you don't need to type so most of what you do is just to scan and the required amount is paid is paid this advantage is it's more expensive than standard credit debit card yeah this kind of system is more expensive then you have limited transaction amounts you can do and it might also be easy to hack because of the radio waves some people can easily hack into that because of the wireless technology now an exam question on that we have contacted debit cards are replacing standard debit cards some countries are introducing contact debit card transactions at atm machines give three disadvantages to the customer of using these cards at an atm now the card may be read accidentally that's true that's a disadvantage uh it's a contactless device you don't need to get for so meaning wireless so people can easily happen to wi-fi networks if they are not well encrypted only small amounts can be withdrawn yes that's also the issue they don't allow it for a large amount of withdrawals also a security measure to ensure that even if they're hacking to your card they shouldn't you know then we have more chance of fraud if cat is stolen yes people can steal your pattern do transactions even from a distance devices can read the cat wireless to steam it yes that's also a disadvantage now the next direct data entry device we want to look at is the chip and pin reader the chip and pin reader is also a direct data entry device so simply you have your card the chip and pin reader has a card slot here you this is your card you slot your card into it and then you it has a screen which displays whatever you're doing when you slot your card maybe you enter your pin if the pin corresponds to the data stored on the card it takes that in if you have to pay for something maybe you enter you you enter the amount and then you press enter and that particular amount is deducted so you could find you mostly find this in places like restaurants supermarkets some travel agencies use it in many other areas so what are some advantages of cheap and pin readers uh they are more secure than the contactless card system they are also more robust system than magnetic stripe readers true uh disadvantages pin can easily be stolen when typing it yes somebody can watch your pin when you're typing it so it's always nice to you know kind of hide hide your pin pin can easily be forgotten that's true some people tend to forget things easily so that's also a disadvantage now the next direct data entry device we have is the radio frequency identification read as the rfid so basically they use radio waves to read and capture data stored on the tab they contain microchips which can also store data for they can also store they can process information and they also have an antenna which they use to capture and to receive and transmit data mostly you find a rfid reader readers are being used for they are mostly used to track livestock by farmers and then you also find them using retail shops or or libraries to track things like things in the shop different items in the shop or books in the library um RFID readers basically the advantage is they can read data from several meters away Yes, fast data reception and processing, reliable and robust.
They can also allow bidirectional data transfer, meaning you can transmit and receive. Disadvantages, they are more expensive than barcodes, they are prone to collision, or there is possibility of interference between tags. Because of the wireless, if there is too much projection of the same type of cards or signals in a certain area, there is bound to be interference.
So it's also relatively easy to jam. uh this form of this kind of signals and also lastly they can also easily be hacked so those are the advantages of this technology now a simple class question that's for a question from just last year so they say a library is considering the way it issues issues books the library owners are planning to use our id rather than barcode to describe the advantage of singapore so it's kind of a comparative answer you have to give here for correct good points from here will give you all your marks so you can always read over this around it to go over that so just for let me talk about two or three points rfds rfids are faster to read than barcodes that's true you can even read it from a distance i remember this scanning is more accurate than backwards that's also true i already does not need line or side to read but backwards does as i just said you can read from a distance that's an advantage um now Another type of direct data entry device we have is the optical mark recognition or it could be an optical mark reader. So what the optical mark reader does is it reads marks written in pen or pencil on special pieces of positional paper.
So the device is designed so that it can recognize these marks once you pass the paper through it. So we mostly use these OMRs. to read questionnaires for mcql marking and maybe voting area voting for voting purposes now what are some advantages of omrs they are very fast way of inputting results into a computer yes so you just pass your paper through here once the paper passes through what happens is once the paper passes through what happens is it marks the whole paper if you're marking a paper and immediately the results are also recorded.
It's more accurate than monotype key in data. That is true. For disadvantages, forms must be carefully designed and positioned accurately and positions accurately placed for marks to be made for easy recognition. Yes, so this is a disadvantage. If the forms are not carefully designed and also if you make marks on different places, they might not record that as the max so you can lost max from just maybe putting them in a wrong position must have been difficult to read if not done with good in opens yes usually this kind of uh it is a form or it's a an example paper answer sheet they usually use a specific kind of pencil which is a very very real readable it's easy to read by the device so that's a disadvantage now We can also compare the optical map reader.
No, I think I skipped the slide. So now the next after the after the optical map reader, the next thing we have is the optical character recognition. So the other one recognizes marks. This one recognizes characters. So this one can convert text on hard copy documents into electronic form.
So if you look here, this is I mean. a certain version type of um ocr so it's scanning this text and sending it to computer and then some can find about mobile apps you just scan the hard copy and then it converts it to text then spatial ocr software for that convert is electronic data from a compatible for other applications it's used in airport for processing of passport yes in airport you find things like this they can scan your passport capture your data and use it and keep it for whatever security purposes so you can also use to convert documents electronic form now what are some advantages of i think there's a mistake here advantages of ocr fast data entry system than manual methods less error no monotyping so you don't need to type your scan disadvantages of ocrs difficulty in reading some handwritten handwritings or data Still not very accurate as needed so this device still need to be upgraded. Now we can compare the OMR and the OCR.
No one reads marks, the other one reads characters. So let's compare them. The OCR is more accurate data reading method than OCR. The OMR is more accurate compared to the OCR. Then we can see that the OCR is more accurate.
is more accurate than manual typing but issues of recognizing all handwritings still exist yeah so the ocr you know it does character to text so it has some issues recognizing or all handwritings then the omr is easier and faster to complete forms yes the ocr less easier to complete forms compared to the omr simply detects marks on page and compares position with stored template Yes, that's correct. Why only for the OCR it detects written characters? Reading can be difficult if writing is not very clear.
yes so that is also something uh now the omr is good for using marking multiple choices and mutual papers why the ocr is good for converting documents to one ed edible electronic form so basically these are just some points you can use to compare these two devices if you are asked to now another very important type of direct data entry devices barcode readers and scanners you find this almost everywhere so the scanner is used to scan and read information from backwards on various categories of products this is the scanner the black thing the uh being held here while they the these lines find you see on the package at the backwoods so this is a scanner and this is the code so this backwards scanner can read off information from that back so you will find them in supermarkets for product identification tracking and billing you also find them used to track books in libraries now what are the advantages of barcode systems they are faster than monoling key data they are a reliable technology and they allow automatic stock control disadvantages we have relative expensive system yeah it is quite expensive so some people find that as a disadvantage systems can be tricked if barcodes are swapped on products that's true if some products the backwards are kind of pasted so it's possible for you to you know remove this and paste it on a document somebody can that to i mean people have done that to trick your system barcodes can be easily damaged compared to rfid tax or magnetic stripes so that is also a disadvantage now the other category of all the other type of direct data device the quick response this one has become very very common nowadays yeah this one is very very common now and so to quick response code scanners or readers they are you have a matrix like this so this is some form of matrix of field intact squares on a light background so um The black areas actually is the, if you look at it, you see that you have black and dark areas, which all carry information that can be used to get access to all of these dark and white areas carry certain information you can use to get access to applications, websites, products and whatnot. Now this QR code can be used for to to can hold up to 5 4 296 characters compared to 30 digits in barcode so that is a big advantage over the backup rear backwards now we can use this qr code for product advertisement access to system website access and in many other areas now what are the main advantages of qr codes faster and easier to read compared to barcode yes qr codes can be encrypted giving them better protection and backwards yes they can hold much more information compared to normal backwards as i just said here also with disadvantages the multiple qr formats exist so the existence of multiple multiple formats makes it uh quite disadvantage meaning uh it's kind of uh easy to manipulate and other aspects coming or it's difficult to you know fully grasp all this technology the ease of access to different apps to generate qr codes means qr can easily be used to transmit malicious code yes some which is termed a target so some people uh actually use these codes to qr codes to transmit malicious um code so that was it about the input devices so we've looked at manual input devices and we have where you much human effort is needed to enter data into your computer and then we've also looked at the direct data entry devices where little or no money for is needed to enter data into your computer so this is the last part of input devices the next thing we'll be looking at will be output devices and their uses so stay tuned and i'll be uploading a video on that very soon thank you