So, let's take a look at the back of our computer again. Here, you'll see lots of connectors or ports. We can plug in different objects like a mouse, keyboard, and a monitor. These are known as peripherals. A peripheral is basically anything that you connect to your computer externally that adds functionality. You probably used USB devices before. USB, also known as Universal Serial Bus devices are the most popular connections for our gadgets. USB has gone through lots of changes since inception. You most commonly encounter USB 2.0, USB 3.0, and 3.1 in today's system. Here's a quick rundown of the different versions. USB 2.0 transfers speeds of 480 megabytes per second, USB 3.0 transfers speeds of five gigabytes per second, USB 3.1 transfers speeds of 10 gigabytes per second. In the chart, let's pay attention to the details. Using capital M lowercase b forward slash s instead of using capital M capital B to reference transfer speed. These are actually different units. MB is megabyte or unit of data storage, while capital M lower case b forward slash s is a megabit per second, which is a unit of data transfer rate. People often mistake speeds of 40 megabit per second to mean that you can transfer 40 megabytes of data per second. Remember, that one byte is 8 bits, so to transfer a one megabyte file in a second you need an 8 megabits per second connection speed. So, to transfer 40 megabytes of data in a second, you need a transfer speed of 240 megabits per second. You'll also need comparable USB ports to go with your devices. If you connect a USB 2.0 device into a USB 3.0 port, you won't get 3.0 transfer speeds. But you can still use the port since it's backward compatible, meaning older hardware work with newer hardware. The ports are easy to differentiate. Let me show you. In general, USB 2.0 are black and USB 3.0 are blue and 3.1 ports are teal. This may change depending on manufacturers. There are lots of types of USB connectors, and you can read about all of them in the supplemental reading right after this video. Check it out. Back to USB connectors. The most recent one is the type C connector which is meant to replace many peripheral connections. It's quickly becoming a universal standard for display and data transfer. In addition to USB peripherals, you should also be aware of display peripherals. There are some common inputs standards to know. Most computer monitors will have one or more of these connections, but you might encounter some older standards too. DVI. DVI cables generally just output video. If you need to hook up a monitor or projector for a slide presentation and you want audio too, you may be out of luck. Instead, you want to look at one of the following cables. HDMI. This has become a standard in lots of televisions and computers nowadays and outputs both video and audio. Another standard that's become popular among manufacturers is a displayPort which also outputs audio and video. In addition to audio and video, USB type C can also do data transfer and power. As an IT support specialist, you'll work with peripherals like USB devices and display devices a lot. Now, you'll be able to distinguish between the major types. In the next lesson, we're going to learn how our computer initializes all of the hardware we talked about.