OS Interfaces

When we're working on a computer, we're working with that hardware through an operating system. That operating system is called an interface. The interface is what's being presented to us and what we're interacting with. That interface looks different depending on what operating system you're using, and there's two types of interfaces.

The Two Types of Interfaces

When you're on your computer, you're probably using some sort of mouse or touching the screen to move around and interact with it, and what we're interacting with is graphics. For instance, a file or folder: you're touching an icon, and the icon is a folder and it's representing some sort of directory, or it's some sort of file icon and you're interacting with that. What we call that is a graphical user interface. It's an interface that you as a user, you're the user, and you're interacting with graphics on your computer, and so we call it a graphical user interface, or really we call it GUI for short. Even though it's GUI, we pronounce that gooey.

So you're interacting with a GUI on most of your systems nowadays, but that's not always the way it's been. We also have another system that we could interact with, and that is a console, command line, terminal, that we interact with using our keyboards, primarily through our keyboards, and with text. So those are the two different systems that are out there.

A Windows System

Here I'm on a Windows system, and this is a little bit older of a Windows system, but it will still work for our demo here. Really, Windows systems have been primarily GUI since 1995. They came out with Windows 95, and that's when they primarily were GUI interaction rather than having any sort of command line.

So we are on a Windows machine, and what I see here is folder icons. These are representations of a directory, and I open that up and now I can see what's inside of that directory, and these are different programs and they're represented by some sort of icon that's representing each one of these. Most of them are executables. So everything that I'm interacting with is with a mouse and with graphics here. I could use the keyboard and I could scroll through; right now I'm using the up and down arrow keys to scroll through this list right here. But that's not the primary way that I'm interacting with it; really I'm interacting with these graphics.

So if you want to see what Windows looked like before, what we could do is hit this start button right here and type in CMD, and this will open up a command prompt. This command prompt is similar to MS-DOS and the way we interacted with Windows machines before. So what we can do is, here at the demo laptop, I can type in dir and I'll get a directory of what I see here. Maybe I want to get into, let's say, the desktop, so I'm going to do CD desktop. CD stands for change directory, so I'm going to do CD desktop and hit enter, and now I'm in the desktop. I've hit dir, and now I see this Sysinternals Suite, which is this folder that I see graphically on here, but this is the text based version of this. So through this console right here, through this command prompt window right here, I can actually interact with the same files and folders, but with text based rather than the folder based.

A Raspberry Pi System

Here's another example of a GUI system, this is a graphical user interface. This is Raspberry Pi. Raspberry Pi looks a little different, it's Linux based, and we see something similar to the start button up here, and you can see all my programs are in here. So it has some of the same concepts but looks a little different. And then I've created this test folder, and within the test folder I have a document here. So it's all graphical, I can interact with it with my mouse, and it's all graphical.

But it also has this terminal window here, so I can open up this terminal window, and in this terminal window I'm going to do a dir to see which directories we have in here, and we have the desktop. So I'm going to go CD for change directory and desktop, and I'll hit enter here, and dir in there, and we've got that test folder. So here I can see it graphically, and on the command line I can see the text based version of it. So I'm going to go CD test and then dir, and here we've got that document that's inside of there, which is the same one that I see right here graphically. I see it in this command line. So that's two ways of interacting with it.

So those are the two primary ways we interact with computers. Through a GUI system we interact with graphics; otherwise with something like a console or text based system we're typing out text.