Drivers

Your kernel interacts with the hardware, but of course it doesn't necessarily know every single piece of hardware out there that it can interact with. It needs some instruction on how it's going to interact with this different hardware. Well, that's where a driver comes into play. A driver is some separate instructions on how that computer can interact with the operating system, or how that operating system can interact with the computer.

Why Drivers Are Separate from the Operating System

There's a lot of manufacturers out there for different hardware on your computer, not to mention each one of those vendors, each one of those manufacturers, has a large product line, and they update those product lines. So if we incorporated all of the instructions on how to operate with all of that equipment into the operating system, that operating system would be huge and very problematic.

So what we do is we actually have a separate set of instructions for each one of these devices, so that way when you install something — let's say you attach a flash drive — then what we do is we have a driver that helps interact between the operating system and that device.

One of the advantages of this is when I swap out hardware on my computer, then all I need to do is update the driver for it, and then I can utilize those extra features for whatever I just upgraded. Or there are times when the vendor of whoever created, let's say, the graphics card, maybe they come out with some additional features. They could release those through a driver update, and then we can access those additional features just through that software update that we received.

Default Drivers

One of the problems is your computer has to be up and running in order to update these drivers, and so that becomes problematic if we turn up a computer and then we don't have access to be able to see what's going on, because we don't have any GPU that's running, we don't have a screen that's running, we don't have these features.

So what happens is a lot of these devices have a default driver to get it up and running. The operating system has a default driver as part of it to help run something like a GPU. Then, once you get that computer up and running, now what you do is you go to the manufacturer, whoever created that graphics card, you download the driver and install it, and now you can access the additional features that that manufacturer has on that graphics card.

So there are these default drivers to help us get up and running and started, and then we may want to replace a lot of those default drivers with the actual drivers for the specific hardware to take advantage of the extra features.

Device Manager on a Windows Machine

Let's take a look at a Windows machine and see what it actually looks like on the machine. I'm going to click the Windows button and type in device manager, and open this up, make it a little bit bigger here.

On here what you can see is we've got a lot of different categories. These are the different categories of different components on this machine. So for instance we have display adapters, so I open that up — this is the graphics card right here. Graphics cards are usually one of those things where the driver needs to be updated. We also have here the keyboard and some interface stuff, we've got the mouse, we've got monitors — monitors is something that usually doesn't need to be updated — we've got network adapters, we've got printers, processors, so here's the processor on here. Like I say, some of these you'll find that need to be updated, some of them not.

Let's take a look at the graphics card here. If I right click on here I can go to update driver, and then it will pop up with this update driver. I can also go to the properties here, so I'm going to go to properties, and I find the driver tab. I can see that this driver right now is provided by Intel, what the date of this driver is, some details, and I have the update button here as well.

If I click this update button I get that same window as I had before, and I can either search automatically for a driver — so this would search to see if Windows, or even go online and see if there's anything available for this. Sometimes there is, and it makes it real easy, where you can just click this and it will do the update, and that's great. But other times you have to actually go and download that driver onto the computer and then browse for this.

Also, there are many drivers that you just download the install file, and you double click the install file and then it goes through the install process. There is also sometimes, like Dell — this is a Dell machine — Dell has a utility that you install on here and it will automatically scan for drivers to see if any of them need updating, which can be very handy as well to keep these devices updated.

You also see some things like the resources, like the memory allocation that's specifically for this. So there's some cool, interesting stuff that's in here that you can sort through and look at, but this just shows you all of the devices that you have on your computer and how the operating system needs these drivers.