Hardware Module 2 Introduction

00:01

welcome to domain to off the camp T A I T fundamentals class domain to focuses on hardware

00:10

in Module 2.1 were asked to identify basic wired and wireless peripherals and their purpose.

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So this module we will look at peripherals

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peripheral is anything that can be plugged into a computer using one of its ports. We will look at those different ports in Model 2.2,

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so peripherals would include your keyboard mouse display that you plug in a printer scanner,

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external hard drives or any other bit of hardware you plug into your computer.

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Let's start off by looking at output devices.

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The video I put from a computer is sent to the display.

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Sound is I'll put by speakers,

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and if you want hard copies of what you see on the screen,

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you could use a printer.

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There are three major types of printers and use today.

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Laser printers are used in business environments. They produce very good quality text and simple graphics, but they're not great for printing photographs

01:19

at home. Many people prefer inkjet printers

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thes use liquid ink rather than tona.

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Inkjet printers are almost always capable of color printing

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for printing photographs on glossy paper. Big jets are far superior to laser printers,

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although the printout may become permanent after the Incas dried, though, spilling water on the printout might smudge it. And that's because Liquid Inc is being used.

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Thermal printers are not commonly used in homes or most businesses.

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However, there is one type of business that makes extensive use of thermal printers.

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Receipt printers deployed at the checkout in shops are usually thermal printers.

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Let's start off by looking at laser printers. These are very commonly used in corporate networks,

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and one reason for that is

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that laser printers give the cheapest cost per page,

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and we'll come back to that when we compare the cost to inkjet printers.

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Laser printers use a dry powder called tona.

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The toner is fused to the paper using heat.

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You might have noticed that when paper comes out of a laser printer, it's sometimes warm

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by. Fusing the toner to the paper

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printout has made permanent

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another big advantage for businesses

02:50

in terms of maintenance. The most common type of maintenance required for laser printers is toner cartridge replacement.

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If it is a black and white printer, there is only one cartridge for

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the black toner that you need to replace

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color laser printers will typically have four toner cartridges

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black scion, magenta and yellow.

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Although toner cartridges are expensive maybe just under $100 each.

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Each cartridge can typically print a couple of 1000 pages.

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Therefore, the cost per page is actually lower than for inkjet printers.

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As I mentioned earlier, inkjet printers are frequently found in homes and in small businesses.

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Inkjet printers are incredibly cheap.

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You can pick up a low end one for between 50 and $100. That's around the cost of a single laser printer toner cartridge.

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But of course, that a catch,

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even though in cartridges, are much cheaper than laser toner cartridges.

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They run out much sooner,

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and generally the cost per page is much higher than for laser printers.

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Let's introduce the concept off

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TCL or total cost of ownership here.

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When you're evaluating which type of printer to get,

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you should take into account not just the cost of the printer,

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but also the cost of consumables like ink.

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If you do,

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inkjet printers look a lot less attractive due to their high cost per page

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ink jet printers use liquid ink that it squirted onto the page in microscopic droplets.

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The print head either uses heat or a piece of electric valve to control the flow of ink.

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Because this is ink, you should not use highly absorbent paper for jack printing.

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If you use absorbent paper.

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That tiny, precise dot of ink that escorted onto the page

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infuses into the paper and making the image look a little fuzzy.

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With the right type of paper, however, you can get great results.

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That's why these types of printers are excellent for printing photographs on glossy paper.

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One downside of inkjet printers is that they can be noisy

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as far as maintenance goes. Inkjet printers required more maintenance than laser printers, not least because you end up having to replace the ink cartridges much more frequently,

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plus those tiny nozzles through which the Inca squirted can become clogged.

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The printer will have methods for unclogging the muscles.

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You can either send it a command from your printer from your computer,

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using the properties of the print ink jet printer

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or by pressing buttons on the printer itself.

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The exact method varies from one printer to another.

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You'll need to consult the printer documentation.

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The other problem that can arise is that the print heads for the different colors can become misaligned,

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and again there is usually a routine for checking alignment. Onda adjusting it.

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Here's how to replace in cartridges in an ink jet printer.

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I have to lift up the cover

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printer

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and then you'll see there's an LCD panel and I'm going through the menus and choosing to do cartridge maintenance.

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So the carriage moves out

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to where I can access the cartridges.

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The cover off

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unclipped the cartridge I want to remove up to change,

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and at this point I would dispose of the old cartridge. And who said a new one?

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Slip that into place

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and then pressed the appropriate button to indicate that I've finished.

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At this point, you're going to see lots of movement

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and lots of noise as

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it primes the cartridge ready for use.

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That's usually takes a minute or two.

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As you can see, this is noise against well.

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So as I mentioned earlier, the most common used for thermal printers is for printing receipts, and shops

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note that thermal printers do not use Toner or INC

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instead, the paper is heat sensitive,

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and the print had hits up tiny dots as it moves across the page, creating the ridges on the paper.

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Therefore, the consumable in this case is the thermal paper that you have to buy.

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One problem with thermal paper is that it's not very stable.

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If stored for a long time, the printout can fade. You might well have had this experience where you have stored a receipt away

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and a year or so later. When you go to get that receipt out,

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you find that all of the black has faded away and you just got a black bit of paper

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Onda. The other problem is, if you expose the paper to heat,

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the entire page can turn black.

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Another type of thermal printer uses wax to create the printout. The wax is melted onto the paper.

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This type of printer was popular for creating photographic quality color print types.

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These days, inkjet printers are a simpler, cheaper way of creating photographic quality printouts,

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so let's move on and look at display devices.

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Historically, C R T monitors were used for display devices for computers.

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C R T stands for cathode ray tube,

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similar to the old style TV's. They were big and bulky and generated a lot of heat.

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These days, flat panel LCD monitors are almost universally used.

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Some of these flat screens are touch sensitive, settle on smartphones and tablets, but also your laptops.

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You could also get touch screens for desktop peces

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Projectors can also be used when you need to project a movie or presentation onto a large screen.

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When comparing displays.

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Here are a few technical specifications to consider.

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Firstly, the screen resolution.

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Ah, high resolution is better.

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Images are much more sharply defined and less blurry in high resolution

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resolution is expressed in pixels.

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The pixel is an individual dot

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The more dots there are, the higher the resolution.

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What is commonly referred to as full high definition

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means that there are 1920 pixels across in 1000 and 80 pixels down.

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That's a total of over two million pixels.

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The response time indicates how quickly a pixel can change color or brightness.

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High end displays can approach one millisecond response time.

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The response time effects How good, fast moving video looks on the screen.

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Gamers play games on their computers. Will try to get displays with the fastest response times they can.

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Another specifications to look at is refresh frequency

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that measures how many times a second the images updated

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again, gamers will go for the highest they can afford.

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But for most of US, 60 hertz is more than adequate,

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but 60 times a second.

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The older type of display was the C R T type.

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They worked by firing electrons of the inside of the screen.

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If you were to look closely,

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you would see that the screen is made up of red, green and blue dots.

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There are three separate electron guns, one for each color.

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When a gun fires Electron said the dots, the appropriate color lights up.

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Bear in mind that all colors are a mixture of the three primary colors red, green and blue.

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By varying the amount of each color, we can create any color we like on the screen.

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This, though, is pretty much a legacy technology, and you're unlikely to come across Seattle monitors or TVs these days.

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C. A T monitors were big and heavy,

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used a lot of power

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and suffered from burning.

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Burning refers to

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If you leave a static image on the screen for long enough,

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it can burn itself into the screen.

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That's why screen savers were invented.

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What screen savers do is they put moving images on the screen when your computer's not being used,

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and that avoids a single image getting burnt into the screen.

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The most common type of display today, though, is Theo LCD flat panel displays.

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LCDs do not emit light,

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so the LCD panels have lighting inside the basil that surrounds the screen and shines into the panel.

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Earlier displays used fluorescent lighting,

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which would, as it started to age,

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get dimmer and finally start flickering

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Modern panels. Use L L E D's,

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which don't suffer from these problems.

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The liquid crystals are manipulated through electrical signals do either block or reflect the light that's shining in from the sides.

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A newer type of flat panel display is known as I P s, which stands for in plain switching.

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This gives better color rendition and better viewing angles.

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That means if you look at the panel from an angle, the image is still clear.

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Um, with the older style of LCD panels.

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If you were looking head on at the panel then you would see a clear image. But as you move the way to the side and looked at it from an angle,

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then the image would become darker.

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I PS panels give you much better angles, wider angles from which you can view the image.

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So

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here's a few points about LCD displays.

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They're much smaller and lighter than a C R T display.

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They use much less power and therefore generate less heat.

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They're much less susceptible to the image burning problems that I mentioned with C. Artie's.

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They are easier to recycle,

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and they have high resolution and do not flicker.

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One of the problems with C R T monitors wasif there refresh frequency was too low. There would be discernible flickering on the screen, which, actually, you know, created problems. For some people,

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there was this up susceptible to it.

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The latest display technology is the use off OLEDs, which stands for organic light emitting die outs.

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Being knew, this type of displays more expensive,

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so it has been used for smaller screens like smartphones and tablets.

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But surprisingly, it's also made its way onto large screen TVs and curved TVs.

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Oh, lead computer displays are slowly starting to appear.

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Unlike LCDs, OLEDs do not do admit their own light, and therefore no separate lighting is required for a Nolan display.

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Let's compare old leads to LCD panels.

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They consume less power than LCD panels

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that have deeper blacks and higher contrast than LCDs, which just means everything. This looks a lot clearer.

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As I've already mentioned, they are more expensive than out CDs currently,

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and oh, led screens can be flexible.

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So we now have the latest generation TVs with curved screens,

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and one or two computer displays like that have started to appear a swell

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in the future. It may be possible to print old heads on to virtually any type of material,

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so the display could be

16:03

like a flexible piece of plastic that you could just roll up like a magazine.

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Another type of display is a projector.

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Digital projectors can be connected to a computer using the same ports and cables that display monitors. Use

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projectors work by having a very bright light shining through an LCD panel.

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In the past, the light bulbs, or halogen or similar technologies and the bulbs had a useful life of a few 100 hours and we're expensive to replace,

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but we're increasingly seeing Led is used these days.

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Ladies may have a life for 20,000 hours, so probably as long as your projector lasts.

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The big advantage of projectors is that you can project onto very large screens, which is great for watching movies or doing presentations to large audiences.

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And a projector is much more portable than a large screen display if you need to carry it around with you.

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As with displays, different resolutions are available, so you should check the resolution off the projector before purchasing it.

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And the other big issue is how bright is the projector.

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The brightness of a projector is expressed in units called lumens.

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For a brightly lit room,

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you would want projectors capable of 2000 or more lumens.

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But if you're going to be only projecting in darkened rooms, you know, with the shades down and the lights off,

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then 1200 lumens might be quite adequate for that.

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So you really need to think about in what kind of environment are you going to be using these projectors?

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Another type of output device is a speaker.

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Most desktop computers do not have built in loud speakers.

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Many external speakers are available with built in amplifiers and even subwoofers.

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You can plug those into the audio out sockets in the computer.

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Laptops, tablets and smartphones have built in speakers,

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but would benefit from connecting to external louder, better speakers.

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One connection method. You can use his Bluetooth if the speaker supports that

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with Bluetooth pairing, the speakers don't need to have any wires connecting to the computer because the sound is sent through Bluetooth to the speaker.

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Next, we're going to look at input devices.

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The oldest input device used was a keyboard.

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And remember, the earliest computers and operating systems did not have a graphical interface. So the keyboard was all you needed doing. Put anything into the system.

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Once we had graphical interfaces, though, we could use a mouse

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apart from a mouse. There are other pointing devices, such as track prides and track bowls, so we'll take a look at those as well.

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To input images. We can use scanners and webcams,

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and to input sound. We can use microphones.

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We'll take a look at each type of input device in the next few slides,

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but let's start with the keyboard

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keyboards are used with every type of computing device desktops, laptops, smartphones and tablets.

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Some, such as laptops, have built in keyboards.

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Desktop computers have external keyboards that plug into the USB port.

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In the past, PS two connectors were used, and you see those here, the purple in the green.

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These were six pinned in sockets.

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Purple was for the keyboard connection and green for the mouse connection.

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But, as I said, mostly these days, keyboards and mouse are plankton using USB ports.

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Sometimes smartphones have an actual physical keyboard that slides out.

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Most likely, though, the smartphone or tablet will use a soft keyboard

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by soft. We mean it's not a physical keyboard, it appears on the screen, and you can touch the screen in order Type.

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If you have a Bluetooth enabled keyboard, though

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you compare most mobile devices to that

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in order to make it easier to input a large amounts of text

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with graphical operating systems, you need some kind of pointing device.

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The most common one used is a mouse.

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Originally, the mouse had a rubber coated ball underneath it that would move as you move the mass around

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the bold moved horizontal and vertical rollers within the body, and that was used to track which direction you were moving the my sin.

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One problem that was common was that the ball would pick up dirt and dust and transfer it to the rollers,

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so you had to regularly take out the ball and clean it on the rollers.

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Fortunately, that mechanism was replaced by led or laser technology.

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In this case, a light shines down onto the desk,

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and it's reflected back and picked up, and that is used to track movements of the mouse.

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You would connect the mass to the green PS to port on older systems. But today, as with keyboards, the mask connects to the computer either through a USB port

21:44

or if it's a wireless mouse using blue, too.

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A track pied is a

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common pointing device used with laptops.

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It's a touch sensitive panel that sits in front of the keyboard,

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usually with two buttons that emulate the left. Click already right. Click with the mouse.

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If your device has a touch screen, it may come with a stylus.

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A stylist is used just like a pen. On paper.

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You can write on the screen

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for example, to add comments to a document.

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Or you could highlight text

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or mark up the text, make corrections and so on.

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Plus, a stylist is also great for budding artists as they can draw directly onto the screen.

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No, that not all touch sensitive screens are designed to work with the stylus.

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Most just allow the use of a finger rather than a stylus.

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A pointing device favored by gamers, Games players is a joystick

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modeled on the joystick that pilots might use to fly a plane

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in legacy systems. There was a special connector that was used to plug in a joystick or some other type of games controller.

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These days again,

23:25

they just plug into a USB port.

23:30

And as you can see, that may have a huge array of buttons on there.

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And a lot of those buttons can be tailored to the particular games that you're playing.

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So, for example, you wouldn't configure one button to make your character jump another button to fire something and so on.

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And obviously, moving the joystick around moves the character or around on the screen as well.

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Another pointing device that is a straightforward replacement for a mouse is a trackball.

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It's sort of like an upside down. Most

24:06

you use your finger or thumb to rotate the ball, and you can see in this illustration it's right.

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The trackball also has left and right click buttons, just like a mouse

24:18

and possibly a scroll wheel, just like a mouse

24:26

moving on from pointers and looking at in putting images into your computer.

24:32

So scanners are used to input images off documents or pictures.

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Some scanners have chic feeders,

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in which case you can put in a stack of pages, and it pulls each page through and scans it.

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If your scanner doesn't have a sheet feeder,

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you lift up the Platen and lay down the sheet of paper that you want to scan,

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so you have to scan one page at a time.

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This is not efficient if you regularly need to scan large numbers of pages.

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In that case, it's worth investing in a scanner that has a sheet feeder.

25:12

The use off sound as an interface to computer devices is becoming widespread.

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You speak to your device.

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You could do that to issue commands such as open Power Point.

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You could also use that to dictate words that that are then converted to text and entered into documents.

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This technology is in many ways, in its infancy. Speech recognition is not yet perfect, as you will see in this video, where I attempt to dictate some notes into note pad,

25:48

Open note pad.

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Okay, opening note pad.

25:57

To be or not to be.

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That is the question

26:03

period.

26:06

Whether tis nobler in the mind

26:10

to suffer the slings and arrows of outrageous fortune

26:21

that you can see, I had to edit the text.

26:26

Microphones are built into devices like spot phones, tablets on laptops.

26:32

For desktop computers, you can plug in an external microphone

26:37

with external microphones. You can purchase, you know, low quality cheap ones, but also high quality professional microphones, depending on the kind of sign quality you need when recording

26:49

microphones are also often built into webcams, which we're gonna look at on the next slide.

26:57

So webcams provide a way of inputting

27:00

images or videos.

27:03

Um, you could also use them for video chatting with tools like Facebook Messenger

27:10

or Skype,

27:11

and you can use them for video conferencing.

27:15

Just as with microphones, Webcams are built into mobile devices

27:22

for desktop computers, you can get an external Web common. Plug it into the USB port.

27:27

When purchasing a webcam. Look at the stated resolution. Usually expressed is the number of mega pixels.

27:34

The higher the number, the higher the resolution image you can get.

27:38

You might also see the frame rate is stated.

27:42

This indicates how many times a second it can capture the image for video

27:48

again. The higher the value, the better quality video you will get.

27:57

Some devices can be used both for input and output,

28:02

so let's have a look at these. These would include faxes, external storage and media players,

28:12

although up till now I've mentioned printers on scanners as two separate devices.

28:18

Often these capabilities are combined into a single device.

28:22

These are referred to as multi function devices.

28:26

Not only do you save space with such a device,

28:30

but it also allows you to use it as a simple photocopier.

28:36

Faxing was a popular way of transmitting images off documents using a phone line.

28:42

Many of these multi function devices can act as a fax device if you plug them into the telephone Jack when your wall.

28:49

In that case, the device can vote send and receive faxes.

28:53

Faxing, though, is a fast fading technology.

28:57

Today we can easily send a copy of an image or document to someone by capturing the image. Using a camera or scanner

29:04

and then just attaching it to Anne about

29:14

the internal storage in a desktop or laptop is usually a mechanical hard drive.

29:18

These cannot be easily removed or expanded.

29:22

This is particularly true of black tops, where it's often difficult to actually open it up and get inside and find the hard drive.

29:30

But even with desktops where the hard disk is considered in fr yu, a field replaceable device or unit,

29:38

it is often a fiddly job.

29:41

You have to make sure you have enough spare data and power cables to add a drive,

29:47

and you have to open the case and install that you drive in an available Dr Bait.

29:52

External storage provides a convenient way of copying and moving data from one device to another.

29:59

You can buy an external drive, which you simply plug into an available USB port.

30:03

Smaller external drives draw power from the USB connection

30:08

for larger drives. They will often come with their own external power supply adapter that you plug into the mains,

30:17

adding external storage can expand the storage capability of a device

30:22

and provides a way of backing up your data.

30:25

Both Apple's OSX and Windows 10

30:29

have the ability to continuously monitor your data folders

30:33

and back up any files you change to that external drive.

30:37

And if you're terrible at doing backups like I am,

30:40

that's a great automated solution.

30:45

An external hard disk is basically the same thing as an internal heart desk, except that it's in its own separate box and often has a separate power supply.

30:57

Like the hard disks in your computer, they're usually mechanical heart discs, meaning they're relatively slow and sensitive to Knox Vibrations, et cetera.

31:07

Sometimes they are solid state drives.

31:11

Solid state drives are much more expensive, but they are much faster and more robust as there are no moving parts to damage in a solid state drive.

31:26

Flash memory, also known as memory cards or flash drives,

31:30

also have no moving parts. Just like solid state drives,

31:34

however, they are generally much slower and cheaper and have less capacity than a solid state drive.

31:44

These are really very useful for moving data around

31:47

so you can take

31:48

a one of these flash memory devices, plug it into one device, copy data onto it that move it to another device.

31:57

Historically, there have been several form factors for flash drives.

32:01

Compact flash was around

32:04

one and 1/2 inches square

32:07

and became an industry standard.

32:08

At the same time, some vendors such a Sony, produced their own proprietary for months.

32:15

Whichever type of memory stick you have, your computer or mobile device must have the appropriate circuits to actually plug them in.

32:23

Now. One way of getting around that problem. Our USB sticks

32:29

of common implementation for flash drives,

32:32

sometimes known as a USB stick, sometimes known as a thumb drive.

32:37

This does not require any special sockets. Just plugs into any USB port.

32:44

You might want to pay attention to which version of us be is supported by your computer. On the USB stick,

32:51

USB three will give you the fastest connections.

32:59

But today the most popular form off flash drive is what is known as a secure digital memory card, or SD for short.

33:07

Many devices, from smartphones to desktops, have an SD or a micro SD socket.

33:15

Micro SD cards are tiny about the size of a thumbnail.

33:19

They are popular in smartphones and tablets and digital cameras.

33:24

If your computer doesn't have a micro SD slot, which is quite likely,

33:29

you can get adapters that will convert micro SD to a normal sized esty.

33:35

So, for example, if you have a smartphone and you want to copy some of your photographs from it,

33:40

most likely you have a micro SD card in there.

33:44

So you take that out, you plug it into the adapter, and then you can plug it into your desktop computer and copy your files from that

33:54

media players such as Rocco or Amazon Fire

33:59

plug into the H D M eye socket on a computer display or a bottom TV.

34:05

You can use them to receive and view streaming content, such as Netflix movies or music played through Pandora.

34:14

The big advantage of these is that you do not need to connect your PC to the TV.

34:21

You can even set up your own streaming media server in a home network and use these devices to access the video and audio content stored on the media server.

34:31

One way of storing media on a *** small business network is the use of Nash devices

34:45

and as device is an enclosure that has his two or more hard disks.

34:52

The device plugs directly into the network rather than being attached to a computer

34:58

than as and its contents can then be accessed from any device on your network

35:02

so you can watch any videos stored on it. Listen to any music or other audio stored on it, or you can use it as a false ever where you just store your files, your documents and so on, and you can access those from any device on your network.

35:20

Another benefit off Daz devices is that they usually have something called raid built in

35:25

raid stands for redundant array off independent discs.

35:31

Rate can utilize multiple hard disks to provide full tolerance on better performance.

35:37

For example, with what's called raid one or mirroring,

35:42

you are protected against the failure of a single hard disk

35:45

rate. Zero, also known as striping,

35:50

gives you better performance,

35:52

but no for tolerance.

35:54

Right five, which requires at least three hard disks,

35:59

gives you both protection against disc failure

36:01

on better performance.

36:07

Many CDs and DVDs are read only,

36:10

for example, that contain software or music or movies and cannot be updated or changed.

36:17

But you can't purchase recordable CDs and DVDs,

36:22

and the CD or DVD drive in your computer can then right data to those disks.

36:29

This process is sometimes called burning a CD or DVD.

36:34

The latest types of disks called Blue Ray

36:37

that I used for high definition movies

36:39

can store gigabytes or data

36:45

smartphones are listed as input. I put devices by camped here

36:50

in the sense that they output video and audio.

36:53

You can also record sound and images on the smartphone

36:58

so you can use them both for input and output.

37:04

In a similar way,

37:06

touch screen displays are also considered input and output devices

37:10

as an output device. The function just like a display. So you can, you know, watch videos browsed into that and so on,

37:17

but also because you can interact with the screen, either with your finger or a stylus. It's also an input device,

37:28

so we've reached the end of model 2.1, and we looked at various types of peripheral devices.

37:34

We looked at output devices such as displays and printers.

37:37

We looked at many types of input devices ranging from keyboards, the mouse to stylus to even sound,