4.2.1 Windows Operating Systems.txt

In this lesson, we’re going to talk about operating systems. The operating system serves as an interface between the applications running on the computer and the computer hardware. Operating System 0:07-0:40 If we drew this out we would have the computer’s hardware here. The hardware is the motherbo...

In this lesson, we’re going to talk about operating systems. The operating system serves as an interface between the applications running on the computer and the computer hardware. Operating System 0:07-0:40 If we drew this out we would have the computer’s hardware here. The hardware is the motherboard, the CPU, the memory, the hard drive, the DVD drive, and the video card. On top of the hardware, we install an operating system (OS). Because the operating system and the hardware are independent of each other, we can install any operating system, like Windows, Mac, or Linux, onto our choice of hardware. On top of the operating system, we install our applications. Provides Application Platform 0:41-0:53 The first job of the operating system is to provide a platform for our applications. Applications need a place to run. They can’t run directly on the hardware, so there has to be an operating system sitting in between to allow this to happen. Moderates Hardware 0:54-1:46 The operating system also accesses the hardware for the applications. Not only does the operating system provide a platform for the application to run on, but it also provides a way for the applications to access the hardware in the computer. The operating system software includes special routines that allow an application programmer to access certain pieces of hardware in the computer without having to do a lot of work. Let’s say that we have an application that we are writing and we want to be able to send a print job through a USB port on the PC system. Without an operating system, we would have to write the exact instructions for accessing the USB port on the hardware. But with an operating system, we don’t have to worry about that because the person who wrote the operating system included the instructions for accessing the USB port. All we have to do is send the print job to the USB port and the operating system formats the job and gets it to the USB port. Provides Security 1:47-2:09 The operating system also provides security. Any operating system you use may require you to provide some kind of credentials like logging in with a username and a password to use the computer. The operating system checks its database of valid users and their passwords. Then decides based on that information whether or not you can use that computer. This is an important feature because it helps prevent the loss of important data. Manages the File System 2:10-2:38 The operating system also manages our file system. The file system encompasses all the different storage devices that are installed on the computer. The operating system is responsible for organizing and storing the data that you are working on, on one of these storage devices whether it’s the hard disk, or a flash drive. Managing the file system also relates to moderating hardware. Because we are talking about working with specific pieces of hardware like the hard disk drive, a CD, or DVD drive, or a flash drive. Kernel 2:39-3:05 The first component of the operating system is called the kernel. The kernel is the core of the operating system. It’s what’s loaded into memory when the system boots up. The kernel performs most of the critical operating system jobs that we just talked about. It’s responsible for managing the file system. It’s responsible for managing security, for working with the hardware, and for providing a platform for applications to run on. The kernel runs behind the scenes and does the bulk of the work, so you won’t work with it. Utilities 3:06-3:53 Utilities are another component of a typical operating system. The utilities are the parts that you actually work with on a daily basis. For example, if you’re using Windows and you open My Computer, browse your hard drive, and open a file, you’re using a utility. You’re not actually using the kernel but you’re using a utility that’s part of the operating system that’s interacting with the kernel to do a particular job. Most operating systems come with many utilities. Today’s operating systems are huge, in large part because of the utilities that we pack around the kernel. We could draw that like this we have our kernel and then all around the kernel we have many different utilities. Another key component of the operating system is called an interface. The interface allows the user to interact with the kernel and the utilities. There are two different types of interfaces. Interfaces 3:54-4:42 The first type of interface is a command line interface. which we see used more more often on Linux than Windows. If you want to run a program or a utility, you type the command at the prompt, hit Enter and the program or utility runs. Command line interfaces are very powerful. The second type of interface is called a graphical user interface, or GUI. Instead of using a command line, a GUI represents things graphically on the screen. If you’ve used Windows and you’ve clicked on the icons or the Start button with a mouse, you’ve used a graphical user interface. Many Linux systems also provide a GUI that functions very similar to a windows GUI The command line interface and the graphical user interface are both fantastic for their different purposes. Sometimes you need the power and flexibility offered by a command line interface. However, when you’re just doing day-to-day work, it’s nice to be able to double-click on something and have it work. Summary 4:43-5:04 That’s it for this lesson. In this lesson, you learned that the role of the operating system is to act as an interface for applications, access the hardware, provide security, and manage the file system. The components of the operating system include the kernel, which manages the file system and security and works with the hardware and provides a platform for applications to run on. And we use an interface to run utilities and applications that run on the kernel itself.