Peripherals – CompTIA A+ 220-1001 – 3.6

Our computer systems are designed to support a nearly endless set of peripheral options. In this video, you’ll learn about printers, scanners, virtual reality headsets, webcams, and much more.

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There are many different devices that we can connect to our computers and in this video, we’ll look at some of these peripherals. If you need physical output from your computer then you need a printer. Many printers are designed to provide color or black and white output that can provide documents or photos. Sometimes you can extend the capabilities of your printer by having an all-in-one system or AIO.

This is not just a printer, it can also act as a scanner, a copier, and a fax machine. Usually we connect to these printers using a USB connection. Some of these printers can support connectivity over Ethernet or even over 802.11 wireless. And if you have systems that support mobile devices, they may also include Bluetooth or infrared capability.

Scanners allow us to take a printed document and get it into our computer, usually over a USB connection or over 802.11 wireless. There are different form factors for these printers. There might be an all-in-one that has the scanner built into this printer combination device, or it might be a flatbed scanner that’s easier to scan more bulky devices.

The all-in-one device might also include an ADF, or an automatic document feeder, so you can put a large number of papers in and have them all scanned automatically through the scanner itself.

Here’s a flatbed scanner which can scan a single sheet of paper, or we can put a book or some other large bulky item on top and scan it using the flat bed scanner.

If you work in a warehouse or use a point of sale terminal, you’re probably also using a barcode reader or a QR code reader. These are usually connected to your computer with serial connections, or these days, USB connections. Or with your mobile devices, these may be 802.11 wireless devices.

Of course, this functionality has even come down to our mobile phones, where you can read barcodes and QR codes with the camera that’s on your mobile device.

Perhaps the most popular output device on our computers is our display. These monitors are providing the output from the computer and we connect to these over many different kinds of connections. We commonly use VGA, DVI, HDMI, or DisplayPort to connect to our display devices.

There are, of course, many different standards available, not just in our connectivity, but also in the sizes and resolutions available, which makes it easy to find the exact display device for our requirements.

A relatively new peripheral for our computers is the virtual reality headset. This headset determines everything that we see, effectively putting us into this virtual world. We’re able to control the virtual world with motion tracking. Not only motion tracking on our hands, but other parts of our body, as well. And it’s able to track not just the XY but also the z-axis to know exactly what’s happening with our body while we’re using this system.

The technology behind virtual reality is still emerging, but we’re seeing VR being used for gaming education, art or even travel applications.

Some of our desktop and server devices may use optical drives or DVD drives that allow us to read and store information using light. This optical drive is able to read the information by looking at bumps or discoloration on the optical media itself.

These optical drives support both reading and writing of information, which means we can store a large amount of information as backups. But you can also create this as read-only media, where once you put the data onto the optical drive, it can’t be changed. This is especially common for video distribution or environments where the data must not change after it’s been written.

There is a limitation to the amount of data that you can put on a single optical drive, the highest end being a dual-layer Blu-ray, which can support up to 50 gigabytes of information.

Another popular peripheral for your computer is a mouse. It usually connects to your system with a USB connection or there might be an adapter for PS/2. Your mouse might be wireless, which means you might even have a wireless connection through USB on your computer.

The mouse that we use today is usually an optical mouse with a limited number of moving parts. That light is used to determine if the mouse is moving, which can sometimes cause problems on a glass top. Fortunately, there are manufacturers that make a mouse that is specifically designed to work on a glass tabletop.

If you’re using a mouse, then you’re probably also using a keyboard. Most of our keyboards connect through USB, but if you have an older system, you may be plugging into a PS/2 interface. Most keyboards will work without any special software. But if your keyboard has additional capabilities, you can see additional buttons at the top of this keyboard that start different applications or change some of the media settings, than you might want to install the software or additional drivers that enable those capabilities.

If you’re using a laptop, you might not have enough room for a mouse. In those cases, you may be using a touchpad. This is usually a piece of hardware that is integrated into the keyboard area, but could also be a standalone device, as well. It usually connects through USB or Bluetooth if you’re connecting externally.

This effectively replaces a mouse. So you don’t need a separate mouse if you’re using a touchpad. And you can see it uses no additional space or requires any room to move around on a desktop.

Another type of pad that is usually an external pad is the signature pad. We’re usually paying for things electronically these days, but we often still have to provide a signature. So it’s common to see the signature pad available with a digitizer and a stylus so that we can sign a form without having an actual form in front of us. These usually connect to your computer over USB and there are usually specialized drivers for your signature pad.

If you’re a gamer, than you’re probably already familiar with connecting a gamepad, a joystick, or some other type of gaming peripheral to your computer. These are usually connected to your computer through a USB, and they’re almost exclusively used for gaming.

We are increasingly using video conferencing on our computers these days, and it’s common to see webcams either as a separate peripheral or built into our mobile devices. If it is a device that is external, it’s usually connected over USB, although there are some models of webcams that will connect over 802.11 wireless.

These are more than just cameras, they also include audio input and they’re usually specialized drivers or specialized software that enable both the visual and audio input. If you have a laptop, you may have a webcam built into the laptop itself. This laptop has a webcam right in the middle. It has a tally light next to it that turns on with the webcam is in use, and this particular laptop also has audio input. There’s a left and right microphone right at the top of the screen.

If your laptop or desktop computer doesn’t have a built-in microphone, you may want to plug-in an external microphone. These usually connect over analog connections using TRS, or the tip/ring/sleeve jacks. Or if it’s a digital microphone, it may already come with a USB connection.

If you want to hear what’s coming out of your computer without having to use headphones, then you’ll need a good pair of speakers. These are analog output devices that usually connect over TRS, those are the tip/ring/sleeve jacks that are in the back of your computer. There is usually an option to have speaker output or an audio adapter that has speaker connections on it.

If you want to combine both a headphone and a microphone in the same unit, then you want a headset. Headsets can be used for desktop, use they can be used on mobile devices, and they often connect over a USB connection. There might be multiple TRS plugs, one for the headset and the other for the microphone, or they may be connecting over Bluetooth. This wireless connection is very common for mobile devices.

This allows you to be hands free as you’re listening in through the headphones and talking through the microphone. This is great if you need access to the keyboard while you’re on the phone, or if you need to communicate to others while you’re in a game.

If you’re in a conference room or a large speaking environment, you may be seeing the output from a computer being projected over a digital projector. We sometimes refer to these as LCD projectors, although the technology used inside of these devices may not necessarily be using LCD.

The type of lamp that is inside of these projectors has to be very bright. It’s very common to see a technology called metal-halide lamps. These are, of course, very bright, but they also get very hot and it’s common to see the brightness of these lamps measured in lumens. These are not the type of lamps that you would use for consumer purposes. These lamps are usually very expensive and they can range from $35 to $350 US.

For that reason, you’ll notice that when you power off a digital projector, there’s still a fan that will continue to run for a number of minutes to help cool down that lamp. For that reason, you don’t want to simply unplug the digital projector when you’re done. You want it to shut down normally and continue to cool that bulb.

If you need to move a large amount of data from one computer to another, it’s common to use an external storage device. This is usually a device that is very small. It connects to your computer over USB and inside of this device is usually a hard drive or an SSD.

If these are very large drives or you need higher bandwidth than what USB can support, you might also find external storage drives that support Thunderbolt or eSATA. These external storage devices make it very easy to move very large amounts of data from one place to the other, and for that reason, these can also be a very significant security concern. It’s not unusual in some high security environments that all of these external interfaces are disabled on the computer to prevent anybody from using an external storage device.

If you’re working in a data center, you may have tens or even hundreds of servers that you need to connect to, but you don’t want to have tens or hundreds of keyboards, mice, and displays all set up to be able to connect to all of those devices.

Instead, you might use something like a KVM. KVM stands for keyboard, video, and mouse. You would plug-in a single monitor, a single mouse, and a single keyboard and then simply plug-in those connections from all of the other devices in your data center. From there, you can push a button or use a keystroke on a keyboard to electronically move between all of these devices, all by using a single keyboard, video, and mouse connection.

If you’re working in a retail environment, you’re probably using a magnetic reader or a chip reader as a point of sale terminal. This is a way that you can use a credit card or a mobile device to be able to pay for any type of product or service.

There are a number of different ways to get information into this point of sale terminal. One is using the integrated circuit that’s built into your credit card by sliding it into the reader. You’re able have a physical connection to that integrated circuit.

If your card doesn’t support or have an integrated circuit, you can always use the magnetic strip on the back and slide the card down the magnetic strip reader on the side of the point of sale terminal. If this card reader is physically associated with a point of sale terminal, it’s usually connected over a USB interface.

Your point of sale terminal may also be able to accept payment using NFC, or near-field communication, where you’re able to put a mobile device very close to the terminal and be able to transfer your payment information that way. This is built into many phones and many payment terminals are already accepting these NFC payment methods.

This near-field communication also allows for other functionality with your mobile device. For example, you can now use your mobile device to unlock a door using NFC.

This embedded circuitry that we’ve seen in credit cards can also be used for other purposes, as well. A smart card reader that’s in a laptop or a desktop computer would be able to read the information on this integrated circuit and be able to use that as a form of authentication.

You may have usernames and passwords that you can provide, but it may also ask you to insert your card into the smart card reader as another form of authentication. These readers are sometimes built into a laptop. so when you sign into the laptop, you simply slide your card into the side. Or if you’re on a desktop computer, there might be an external reader that’s connected to the desktop computer over USB.