Operating Systems Overview – CompTIA A+ 220-1002 – 1.1


Why do you need an operating system? In this video, you’ll learn about the fundamentals of Windows, macOS, Linux, and more.

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As you go through your A plus studies, a lot of what you’ll be learning revolves around the operating system. The operating system allows us to control the hardware of our computer. So our hard drives, and our memory, and our CPU you can all communicate back and forth to each other using this operating system.

The operating system is also where all of your applications will run. So anything that you’re doing in a spreadsheet, in a word processing document, or in a browser is all going to execute inside of your operating system. This operating system is also a way for us as humans to be able to interoperate with this technology. The operating system may be at a command line where you type everything in using your keyboard. Or it may be a graphical user interface where you use icons and a mouse to be able to use this technology.

There’s some common features that you’ll find in any operating system that you happen to use. One of these features is file management. You’re able to store a document or a spreadsheet onto the storage capabilities of that operating system. And then you can delete that file, rename that file, or manage where that data happens to go. An operating system is also going to provide a way to run applications. This means not only is it going to display that application on the screen, there’s going to be a lot of interaction between that application and the memory that you’re using. Or there may be files that are spelled out to disk using swap file management. And then swap back in as you’re using other parts of that application.

As you’re using this application, you’re storing information on hard drives. Perhaps transferring information to a USB. There’s going to be a keyboard and mouse that you’re using. And all of this hardware and software works together by using the interactions of that operating system. And there needs to be some way to manage the overall operation of the OS. The operating system will usually include programs or utilities that allow you as the end user to be able to monitor and manage any aspect of that OS.

One of the most popular operating systems is Microsoft Windows. Not only are there the traditional desktop operating systems for Windows such as Windows 7 and Windows 10, they’re also server versions of Microsoft Windows that are used to manage very large scale applications in the data center. The advantages of Microsoft Windows is that it has a huge support from the industry. Most applications are automatically written to run in Microsoft Windows.

You also have many different options for the type of Windows that you’re using. There’s versions of Windows that are designed to be use at home and other versions of Windows that are designed to be used in the data center for large scale applications. Unfortunately, having such a popular operating system with such a large number of installed systems means that you’re also a very big Target for security exploitation. The bad guys know that if they can find one way into Windows, then they’re able to take advantage of many millions of desktops around the world.

Another challenge with Windows is that it has to support a wide variety of hardware. So many different monitors, many different video cards, different storage devices, and different types of printers all have to interoperate and work properly in this single operating system. Here’s a screenshot of Windows 10. You can see the menu along the left side. You’ve got a search bar at the bottom, and other icons that you can choose here to quickly access the applications that you need.

Another popular operating system is Apple’s macOS. This is primarily designed as a desktop operating system designed to run on Apple hardware. Apple’s macOS is designed for ease of use. And because you’re running on Apple’s hardware, you know that the operating system and the hardware of that computer will be extremely compatible with each other. This also means you have less support in the industry for applications running on that operating system than something like Microsoft Windows. And with Microsoft Windows, you can choose the components you’d like so that you can build a computer to fit any particular price point.

With macOS the only hardware options you have are those available from Apple. So you may find that your initial hardware cost is a little bit more than if you were to build the system yourself. And here’s a macOS desktop. And you can see there are a lot of similarities between Mac OS and Windows. There’s icons at the bottom that can be used to start applications. You can see the storage devices are listed as icons on the desktop. And in many ways, the similarities are the same between Windows, macOS, and the Linux operating systems.

Another popular operating system is the free operating system of Linux. With Linux, there is no single Linux operating system. Instead there is a combination of features put together into what the Linux community calls distributions. One of the obvious advantages of Linux is the cost. There is no cost associated for using or running any applications on a Linux operating system. Linux also works on a wide variety of hardware so you can build your own computer and run the Linux operating system on top of it.

And the user community for Linux is very large and worldwide. So if you have any questions about the Linux operating system, there will always be someone willing to help. Because Linux is an operating system that relies on this user community though, there are some limitations to the amount of hardware that can be supported. You may find that there is limited driver support for hardware that is not mainstream. Especially for customized or proprietary hardware that might be inside of laptop computers.

You might also find that support options for Linux are also limited. There’s no single Linux company to go to for support. So you have to make sure you have knowledgeable people available to help you with any problems that you might have with the Linux operating system here’s the desktop of an Ubuntu Linux distribution. And as you can see, it has very similar functionality to Microsoft Windows or macOS.

You have the standard icons on the screen that allow you to run applications. Or a search bar at the top so that you can find your documents or other applications all with a few keystrokes. One of the distinguishing characteristics of an operating system is the type of processor that is supported by that OS. There are usually two options to choose from. A 32-bit processor or a 64-bit processor. One of the differences between these two is the amount of information that can be processed or stored by that processor.

For example, a 32-bit processor can store values that are 2 to the 32nd power, which means you get about four billion different values. If you’ve ever seen the amount of available memory that you can put in a 32-bit operating system, you know that it’s about 4 gigabytes of memory. And so you can see that’s exactly where that four gigabyte value comes from. A 64-bit processor can store information that is 2 to the 64th power, which is much larger than our 4 gigabit value with a 32-bit operating system.

In fact, in a 64-bit operating system, it’s about 17 billion gigabytes of information that can be accessed, which is very different than the 4 gigabytes available in a 32-bit operating system. This means that theoretically, your operating system running on a 64-bit processor could allow you to install 17 billion gigabytes of memory. In reality though, the operating system probably has a much smaller maximum value. Although certainly much larger than the capabilities you would have with a 32-bit operating system.

Another important consideration when you’re using 32-bit versus 64-bit operating systems are the type of drivers that you’re using in the operating system itself. The driver is special software that allows your operating system to be able to communicate with the hardware of your computer. If you’re running a 32-bit operating system, you have to use 32-bit drivers. If you’re using a 64-bit operating system, you have to use drivers that are specifically written for that 64-bit OS. You cannot use 32-bit drivers on a 64-bit operating system, or vise versa.

You’ll sometimes see the 32-bit architecture abbreviated as x86. If you see 64-bit architectures abbreviated, it’s often abbreviated as x64. Another important consideration between a 32-bit operating system and a 64-bit operating system are the applications that you’ll run on that OS. You’ll find that there are some applications that have been written for 32-bit operating systems. And other applications that have been written for 64-bit operating systems.

If you’re running a 32-bit operating system, you will not be able to run 64-bit applications on it. But if you’re running a 64-bit operating system, you can run either 32-bit apps or 64-bit apps. For example, if you’re running a 64-bit version of Windows, you’ll find that any installed 32-bit applications will be stored in the Program Files x86 directory. And any 64-bit applications will be installed in the Program Files directory.

Our mobile computing devices are getting smaller and smaller all the time. But we want the same functionality on our tablet devices as we have on our desktop systems that we’re using at work. That’s why you’ll find that there are tablet devices these days that run a full blown version of Windows 10 on these mobile tablet devices. These tablets are made by many different manufacturers. But they tend to have the same type of hardware with touch screens detachable keyboards and perhaps a stylus that can be used in the Windows 10 operating system.

Early versions of these tablets used a type of operating system that wasn’t a full blown version of Windows 10. In fact, it was called Windows Mobile. Windows Mobile is no longer in development. And after December 2019, it will no longer be supported by Microsoft. On the handset and mobile phone side, one of the operating systems you’ll commonly see is the Android operating system from Google. This is actually the Open Handset Alliance. And it runs an open source Linux version of an operating system on these small mobile devices.

There are many different manufacturers that make Google Android compatible systems so you’re able to find a mobile phone with exactly the features you want. If you’re an application developer, you can create apps for the Android operating system inside of Windows, macOS, and Linux by using the Android Software Developers Kit. If you’re an end user and you want to install these apps, you can get them from Google Play or from third party sites such as the Amazon App Store.

Apple phones use their own operating system called iOS. This is available on the Apple iPhone and the Apple iPad. It’s based on Unix, and it’s an operating system that is closed source. You don’t have access to any of the source code used in iOS. You’ll also only find iOS on Apple products. You’re not able to buy hardware from a third party and run iOS on it. You can only run iOS on Apple hardware.

If you’re a software developer and you want to create apps for an Apple device, then you’ll want to use macOS as your operating system. And use the iOS Software Developers Kit. To make that software available to the end user, you submit it to Apple. And they must approve your software to be able to have that available for end users. Once they approve it, it’s added to the Apple App Store. And users are able to download and use it on their iOS device.

Google also has their own operating system. This is Chrome OS. And it’s based on the Linux kernel. This operating system focuses around the Chrome web browser. Most of the apps that you’ll use on Chrome OS will all run from inside of that browser. This relatively simple approach to applications means that many different manufacturers can now create hardware that will run Chrome OS. And since the operating system is less demanding, you also will find that the hardware is less expensive.

Because many of the apps and Chrome OS run in this browser, there’s a strong reliance on the cloud. So you have to make sure you have a good internet connection to run many of the apps available in Chrome OS. With so many different operating systems to choose from, it’s important to know where the limitations are with each particular manufacturer’s OS. For example, you have to think about how long a particular operating system will be supported. Different manufacturers have different philosophies around end of life. Some manufacturers like to support an operating system for a very long time. Others support it for a shorter period. And expect that you’re going to upgrade to new hardware when that software hits end of life.

Manufacturers also have a different philosophy on how the operating system itself will be upgraded. With Microsoft Windows, macOS, and Linux you may be presented with an upgrade option. And then you get to choose. Although even those options are slowly migrating into operating systems that will always keep themselves upgraded such as the philosophy found with Chrome OS. Even though these are very different operating systems there are certain types of data that can be shared between the different OS.

For example, it’s very common for movies and music to use a common format that you can watch or listen to regardless of what operating system you may be using. Where you start to run into problems though is with the applications themselves. If an application is designed for Windows, it usually is only going to run in Windows. In some cases you’re able to take the data files that you’ve saved from that application and move the data file to a different application on a different operating system. And that may be a big reason why some web based applications have such popularity since they’ll run in any web browser regardless of the underlying operating system.