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Lesson 2: The Operating System, Storing Data,
and Troubleshooting Your PC
Lesson Introduction
In this lesson we learn about the operating system, which is a collection of computer programs responsible for operating your PC. We take a look at some of the roles the operating system plays in your computer, as well as some of the different types of operating systems that are available.
We also take a look at files and folders which is how data is stored on a computer. We go into some detail about how files and folders are named, file properties, filesystem hierarchy, and also how to search for a particular file. We then take a look at how to back up your data, so that if something goes wrong, you won’t lose any of your hard work, and also how to keep your PC clutter free, by removing unwanted files.
When something isn’t quite right with your PC, that’s when it’s time to put your computer troubleshooting skills to work. In this lesson, you will learn basic troubleshooting procedures to help you try and determine what has gone wrong when your computer is feeling under the weather.
Lesson Learning Objectives
At the end of this lesson you should be able to:
- Describe the functions of the operating system
- Identify popular operating systems used in PC’s
- Identify the various types of operating systems
- Explore how data is stored in a hierarchical filesystem
- Describe how to search for files and folders
- Describe how to back up your data files
- Describe how to unclutter your PC by removing unwanted files
- Explain basic troubleshooting procedures to identify why your computer is not working correctly
Lesson Notes
The Operating System
When a computer first powers up, one of its first tasks is to locate an operating system. The operating system, or OS for short, is a collection of computer programs that are required in order for a computer to be usable.
The Functions of the Operating System
The operating system looks after maintaining your computer, including controlling input, output, and storage devices, and accessing computer networks, such as the internet, when needed. The operating system is also responsible for installing, loading, and running other computer programs (apps).
Device Drivers The operating system is responsible for knowing how to communicate with all of the devices installed in the computer. To do this, it relies on small computer programs, called device drivers, - which contain the specific instructions for communicating and controlling each device. A typical operating system, such as Microsoft Windows, contains thousands of device drivers, in order to be able to access all of the various devices that could be installed in a PC. Without an operating system, every computer program would have to include with it the instructions for communicating with each device that it needs to access.
As you add new devices to your computer such as a flash drive, or a printer, the operating system is able to detect this and will automatically go through a process of determining what the device is and install the appropriate driver for it. At this point the device is ready to be used by any application that needs it, including the operating system itself. Microsoft calls this auto-detection capability Plug and Play.
Managing System Resources We collectively call components of a computer - such as the RAM, processor, and storage - the system resources. The operating system is responsible for managing how the system resources are allocated in order to keep the computer efficiently running. A computer with poorly managed system resources will tend to be sluggish – that is programs may take a long time to start up, and when they finally do start up, they may tend to be slow to perform tasks or respond to user commands, or worst case they may shut down unexpectedly – which is called a crash.
You have probably heard the term multitasking – which means performing more than one task at the same time. When applied to a computer, this means that it can run more than one program at the same time. In reality though, it only appears that the computer is running more than one program at a time.
Before a program is started, the operating system will first copy the program from storage into RAM. It does this in order to make programs runs faster – as RAM is much faster than storage. While the program is running, it will take up space in RAM for both its program instructions, and also any temporary data that it needs.
Computer Program Compatibility with the Operating System
The operating system is a computer program’s doorway to using the various components of the computer. Remember that the operating system includes device drivers, which know how to access the various devices contained in the computer. So in order for a computer program to be able to access a particular device, it must have been written to work with the computer’s operating system. When purchasing a computer program, always check its compatibility list to make sure that it supports the operating system that is used on your computer. In addition to system requirements such as the processor type and speed, and the minimum amount of RAM that is required, the compatibility list will also indicate the operating system and minimum version that is required.
The Operating System Interface
The OS interacts with a computer user via the operating system interface. Early operating systems used what is called a command-line interface. In this type of interface, you interact with the operating system by entering text commands, called command-lines. The original Microsoft and Apple operating system interfaces were both command-line interfaces, and were known as MS-DOS and Apple DOS, respectively, where DOS in both cases stands for Disk Operating System. A screenshot of the MS-DOS interface is shown in Figure 1. This is what you would see when your PC was powered on and finished booting.
Figure 1 - The MS-DOS Command-Line Interface
A partial list of MS-DOS commands is shown in Figure 2. The command “help” was entered at the command prompt to display this list.
Figure 4 - Screenshot of the Windows 10 User Interface
In a graphical user interface, graphics - often called objects or elements – are used to control your computer. There are several types of objects. These include windows, small pictures (called icons), menus, and buttons. All of the objects reside on a screen called the desktop. Examples of these are shown in Figure 5.
Figure 5 - Examples of Graphical User Interface Objects
On a graphical user interface, a small indicator, which is usually in the shape of an arrow and is called the mouse pointer, is controlled by a pointing device such as a mouse. When you move the mouse, the pointer
moves in response. The buttons on the mouse are used to indicate your intent. For example, in Microsoft Windows, if you want to open an application, you would move the pointer over top of the icon representing the application, and then quickly click the left mouse button twice in succession - called a double-click.
Popular PC Operating Systems
Currently the more popular operating systems are Microsoft Windows, MacOS, Unix and Linux, and Google Chrome.
Microsoft Windows Microsoft Windows has been in existence since the 1980’s, and is currently the most popular operating system, with Windows 10 being the most current version.
When you buy a PC, a Microsoft supplied copy of Windows is generally included. So Microsoft makes money every time a Windows PC is sold. Typically, when you wanted to upgrade your PC to a newer version of Windows, you had to buy it from Microsoft. With Windows 10 however, Microsoft has been providing free updates, rather than moving to an entirely new version. So it may be that Windows 10 will be the last named version of Windows.
MacOS Apple designs and produces its own operating system, called MacOS, for its Macintosh line of PC products. MacOS is included with the purchase of a Macintosh. Future versions of MacOS are available for free – that is until Apple deems a particular model of the Macintosh to be obsolete, and no longer provides any updated versions of MacOS for it.
The MacOS operating system has a GUI interface similar to Windows, and so they are both similar to use. A screenshot of a later version of MacOS is shown in Figure 6.
Figure 6 – The MacOS User Interface
The file extension portion of the file name is used to help the operating system identify which program it should use to open a file. The file extension is identified as the rightmost dot, followed by the remaining characters of the file name. So for example, if the file name of a file is Resume.docx, then the name portion of the file is Resume and the extension portion of the file name is .docx (which includes the dot).
Similarly, if the file name is My.Resume.docx, then the name is My.Resume, and the extension is .docx. Note that in this example, there are two decimal points in the file name, so the extension is identified as the rightmost dot followed by the remaining characters, which is .docx, rather than .Resume.docx. Some file name examples are shown in Table 1.
File Name Name Extension Resume.docx Resume .docx My.Resume.docx My.Resume .docx Sales in $.xlsx Sales in $ .xlsx Read Me.txt Read Me .txt Seagull.jpg Seagull .jpg Giant-Turtle.png Giant-Turtle .png Table 1 - File Name Examples
The operating system maintains a list of recognized extensions along with the corresponding program that each extension is associated with. For example, on a PC running Windows, the file extension .xlsx is associated with Microsoft Excel, so whenever a user requests the PC to open a file with the .xlsx extension, Windows will run the Excel program and tell it to open the file.
Table 2 lists a number of file extensions that you will often encounter, the type of file, and the commonly associated program that Windows will open each with.
Extension File Type Typical Associated Program .txt text Notepad .rtf rich text format Wordpad .pdf portable document format Adobe Reader .jpg jpeg image file Windows Photos .png png image file Windows Photos .mp3 mpeg3 audio file Windows Media Player .bmp bitmap image file Windows Photos .mp4 mpeg4 video file Windows Media Player .wmv Windows media video file Windows Media Player .dosx Word document Microsoft Word .xlsx Excel workbook file Microsoft Excel .pptx Powerpoint file Microsoft Powerpoint .zip compressed file File Explorer .html hypertext file Windows Edge Table 2 - Common File Extensions, File Types and Associated Default Programs in Windows
Windows doesn’t have a file association for every file extension type – there would be far too many! Although file extension associations can be changed through File Explorer – which is Windows’ file management program - it is generally not a good idea to change them as it can result in a file type no longer being recognized by Windows.
When creating a file name, any character can be used, except those listed in Table 3. Windows will not allow you to create a file name using any of these characters.
Character Name < less than
greater than : colon “ double quote / forward slash \ backslash | vertical bar ? question mark
- asterisk Table 3 - Characters that Cannot be Used in a File Name
File names are not case sensitive – so for example the file names Resume.docx and resume.docx are considered to be the same file name by Windows. Note however the case that was used when the file was created is what is used when the file name is displayed. So if you originally typed the name as Resume.docx, that is the way it will be displayed by Windows.
File Folders
When a file is created, it must be assigned to a file folder. Each folder is also assigned a name as well in order for it to be located when needed.
Each folder can be assigned to another file folder, and that folder can in turn be assigned to another folder. This creates what is called a hierarchy of file folders, where the folder inside of another folder is known as a subfolder. The top level file folder is always known as the root folder.
Each storage device can contain only one root folder. The root folder and all of the underlying subfolders are known as the device’s filesystem, and since the folders are stored in a hierarchy, this type of filesystem is known as a hierarchical filesystem.
Windows assigns each storage device a unique letter, called the drive letter. Historically the letters A and B were reserved for floppy drives, which are obsolete, so you will not likely see these letters in use anymore. The letter C is generally used to indicate the main storage device, and it contains all of the operating system files. The letter D is often used for a CD or DVD drive. Typically as more storage devices are added to your PC, they will be assigned letters in sequence.
The path is the name given to the order of subfolders that a given file is located in.
Naming Files and Folders
A typical PC has thousands of files, if you include the operating system and installed programs, along with your own data files. Any time you create a file, you should always keep in mind that at some time you will likely want to find it again - so it is best to always give it a meaningful name, and keep it in a folder hierarchy that makes it easy to find – otherwise you may find yourself having to search through countless other files to find it.
As a rule make sure to create additional folders that describe the subject of your files. For example, if you have a collection of photos from various vacations you went on, create a folder named Vacations in the Pictures folder, and then create a separate folder for each vacation in the Vacations folder. Now you can copy the pictures from each vacation into the appropriate folder corresponding to that vacation, such as in Figure 7.
Figure 9 - Accessing the Properties of a File
The File Properties window will now open up, which in this example is the properties for an image file with the name DSC_0045, as shown in Figure 10.
Figure 10 - General File Properties
Clicking on the Details tab will bring up the property details, an example of which is shown in Figure 11. Depending on the file type, the type of detailed properties will vary. In the case of an image, details about the resolution are provided, when the image was taken, and if you were to scroll down, details about the camera make and model, and even the camera settings may be included.
Figure 11 - Detailed Properties of a File
Backing Up Your Data
Many people overlook the importance of keeping regular backups of their data. PC’s are generally very reliable, so it is becoming rarer that your PC will crash resulting in you losing data. However it’s not unheard of to have a hard drive failure, causing a complete loss of data. Simply giving your laptop a severe enough bump while it is powered up can cause a hard drive crash. You may also be unfortunate enough to have your PC stolen or have it infected with malware.
Most businesses have a backup strategy, but it a good idea for you to have one for home as well.
Backup Using Microsoft File History Windows provides a backup feature called File History, which copies your files to an external storage device on a regular basis. To access File History, open the Settings window, by clicking on the Windows Start button and then clicking on the Setting (which looks like a gear. In the Settings windows, select Update & Security. Now select Backup to open the Backup window, as shown in Figure 14.
Figure 14 - Backup Using File History
At this point, you will need to add an external storage device to your PC which you will need leave continuously connected. Now click on “Add a drive” and then when Windows detects the new storage device, click to select it, and Windows will begin backing up your files. By default, Windows will back up files and folders in the Users folder. To modify the selections, click on More Options to open the Backup options window, shown in Figure
In the Backup options window, click on “Add a folder” to add an additional folder to backup. To remove a folder from being backed up, click on it and then click the Remove button that appears. Scroll down to see all of the folders selected for backup. You will also be able to access additional options, including a link to restore files from an existing backup.
Figure 15 - Selecting Folders to Back Up
Backup to the Cloud Unless you keep backups that are offline - that is not attached to your PC - and even offsite, you run the risk of still losing data. For example, if you have an external storage device constantly connected to your PC for backups, and your computer becomes infected with malware, the backup storage device may become infected as well. Similarly, if you have an offline backup device that you keep in your home, it could be destroyed in a natural disaster such as fire or flood, or lost to theft.
Backing up your important files to a cloud storage service such as Microsoft OneDrive or Google Drive, is a solution. These services do have a limited amount of space available for free – currently 5GB for OneDrive, and 15GB for Google Drive, but you can purchase additional storage space for reasonable prices.
Windows System Utilities
Windows includes a number of programs that allow you to monitor and manage the state of Windows. These are known as system utility programs. One of these programs is used to identify and remove unused files from your PC to keep it clutter free, as we discuss next. We will also be showing you how to use the Windows troubleshooter programs later in this lesson, which is another example of system utility programs.
Keeping Your PC Clutter Free As you visit various web sites on the internet, temporary files get stored in your PC’s storage device. Your computer does this so that the next time you visit the website, it will load faster. These files are called cache
Sometimes Windows will restart your PC after taking an update. In this case, it may look like your PC is in the middle of booting, but seems to be stuck. This is often normal, as Windows can sometimes take a long time to install updates. Give your PC plenty of time to start up in this situation – even 15 minutes or longer is not unheard of.
Always try to perform a controlled restart of your PC by requesting the operating system to do it. In Windows, you can do this by clicking on the Start button, then clicking the Power button and selecting the Restart option.
If your PC is non-responsive, try pressing the key combination Ctrl-Alt-Del (which is the Ctrl, Alt and Del keys simultaneously pressed). This should bring up a screen which includes a Power button in the lower right hand corner from which you can select to restart it.
If this doesn’t work, then you will need to resort to a forced shutdown. Only do this when absolutely necessary, because it can result in lost data – especially if you were working on something that wasn’t saved. In most PC’s you can perform a forced shutdown by holding down the power button for several seconds until the PC turns off. Wait a few seconds and then press the power button again to start the PC.
Inspect Cabling and Check for Poor Connections
Another common source of problems is poorly connected or defective cabling. If restarting your PC doesn’t resolve a problem, then check that all cabling is securely connected. Also check for frayed cables. Charging cables for mobile devices such as tablets and smartphones are particularly prone to fraying or breaking internally near the connectors. This can result in intermittent charging problems – sometimes your device will charge and other times it won’t. If you suspect a defective cable, try swapping it out with another one.
If you have an external monitor and the screen goes blank while it is powered on, check that the cable is fully inserted in the connector ports at both ends. Some styles of connectors must be fully inserted to make good electrical contact and the can be easily jarred loose.
Check Network Connectivity
Check to see if you are connected to a network. In Windows, the easiest way is to click on the Internet icon in the notification area of the taskbar. This will tell you what connection, if any, you currently have. An example is shown in Figure 17. Here you can see the PC is connected to a network connection named Henry. To see information about this network, click on the Properties link – below the network name. We also know this is a wireless network since the wireless symbol is present.
If there are other networks available, they will be listed here as well. Make sure you are connected to the correct one.
Also, make sure you don’t have your device set to airplane mode, as this will turn off wireless network connectivity. If you can’t see the Internet icon in the taskbar, but you do see a small airplane icon, this is the problem. Click on the airplane icon and then click on the Airplane Mode button.
Figure 17 - Checking Your Network Connection
Has Anything Changed Recently
If restarting your PC and checking all of the cabling doesn’t resolve a problem, ask yourself if anything has changed recently. For example, did you install a new program or update an existing one? Was new hardware added? Also, Windows frequently receives updates from Microsoft to fix bugs and security problems, as well as to introduce new features, and these updates have sometimes been known to cause problems.
Don’t forget to check with other family members in your home to see if they are experiencing the same problem
- especially with internet access problems. Also, if you have limited bandwidth on your internet, such as 10Mbps or even 25 Mbps, make sure that other members of your household are not running bandwidth intensive programs, especially video streaming apps such as YouTube and Netflix, or are downloading a large program that they plan to install.
Uninstalling a Program If you installed a new program about the time a problem occurred, try uninstalling it to see if the problem is resolved. We will be looking at uninstalling programs in Lesson 4.
Sometimes a program will allow you to perform a repair rather than having to uninstall it and then reinstall it. If the repair option is available, then it will typically be faster to do this.
New Hardware Devices Sometimes adding a new hardware device will cause your PC to behave erratically. If this occurs, First try removing the device and see if that fixes the problem.
When installing a new device, a device driver will need to be installed in order for the PC to control it. This is normally an automatic process, where Windows detects the new device and then finds and installs an appropriate driver to support the device. Occasionally however, there will be an instance where Windows is unable to detect the device, or it may not be able to locate an appropriate driver. In this case, you will be required to intervene. Your best bet is to refer to the device manufacturer’s website for further information on how to proceed.
Research the Problem
If you still haven’t located a solution to a problem, it’s time to resort to doing some research. With the millions of PC users throughout the world, the chances are very good that you are not the first person running into the same problem – and the likelihood of someone having already reported this on the internet is also good.
Figure 18 - Windows Troubleshooters
Learning Activity
The following activities are designed to enhance your comfort level with the lesson’s material, reinforce the topics discussed and prepare you for the lesson’s quiz. They are not to be submitted for grading. You will find the answers at the end of this lesson.
- What does OS stand for?
- True/False – Device drivers are small computer programs designed to communicate with and control a device
- What type of user interface does Windows have?
- Which of the following steps should you take when troubleshooting a computer? a. Restart your computer. b. Inspect cabling for poor connections. c. Check if there have been any recent software updates. d. Ask your brother-in-law if he knows e. All of the above f. None of the above
- You can’t access anything on the internet. What is the first thing you should do?
Summary
In this lesson we learned about the functions of the operating system, including identifying some of the more popular PC operating systems, and some of the various types of operating systems.
Next we learned how data is stored on a computer, in a hierarchical filesystem, including how files are named and placed into folders.
We then learned how to search for files using Windows File Explorer
To prevent data loss, we learned how to create file backups.
To keep your computer clutter free, we learned how to remove unwanted files.
Finally, we learned some basic troubleshooting steps to identify what is wrong with your computer when it is not working correctly.
Next Steps
Now that you have completed Lesson 2 please go to the Assignments folder and complete Quiz 2 as per the course schedule. Once complete, you should then proceed with Lesson 3.
References
Gaskin, S., Geoghan, D., Graviett, N., & Vargas, A. (2017). Go! with Microsoft Office 2016, all in one. Boston: Pearson.
List of operating systems. (2019, September 26). Retrieved from https://en.wikipedia.org/wiki/List_of_operating_systems.
Naming Files, Paths, and Namespaces - Windows applications. Retrieved from https://docs.microsoft.com/en- us/windows/win32/fileio/naming-a-file.
Operating system. (2019, October 11). Retrieved from https://en.wikipedia.org/wiki/Operating_system.
Learning Activity Answers
- Operating System
- True
- GUI – graphical user interface
- e. All of the above.
- See if your computer is connected to a network.
