Tutorial Blog 4: Computer Security and Privacy

Many of us use the internet and store files in our computers on a daily basis. With such a high Internet use, it is inevitable to be exposed to dangerous websites, files, and software. However, we can all protect our computer files from being damaged or stolen by being informed about possible risks that lurk throughout the Internet. By becoming aware of some Internet dangers, you can take all the right steps to assure your computer is safe from malicious users. This blog will discuss some of the most common types of Internet attacks--such as viruses, worms, Trojan horses, and rootkits. It will also give you tips on how to protect your computer.

I'm sure you've heard of the term Malware. But what exactly is it?
Malware is a short name for "Malicious Software" which is a group of programs that purposely modify how computers operate without the user's knowledge. Malware can take over your Internet browser, deviate your search attempts, spit out many pop-up ads, and even keep track of what websites you visit. Sounds annoying and frustrating doesn't it? You're not alone, malware affects an immense number of users every year. Let me introduce you to a few types of malware:

Viruses
Computer viruses are one of the most infamous types of malware. It is a malicious program that infects a computer system without the user's consent. Once it is in the system, it will replicate itself, infect different system files, and then try to spread onto other systems. Many people get such viruses from E-mails and flash drives--which are commonly used mediums. Viruses will eventually slow down your system significantly and may require you to erase all the files on the computer.

Worms
Worms are self-replicating programs (usually on memory or a network) that use up resources and damage many files at a time. A worm is very similar to a virus, however, a worm tends to attach itself to a network and therefore affects thousands of files in a very short period of time. Usually, worms will delete files, or allow its creators to access and control the computer systems--which of course, can be tragic to corporations holding sensitive files on dozens of computers on a single network.

Trojan Horses
Trojan horses are programs that hide themselves within a legitimate program or pretends to be a safe program. The name is derived from the Greek myth of a wooden horse used to invade Troy. The program pretends to be harmless to the user, and can deliver many harmful attacks such as viruses, worms, and the like. A few source examples include friendly email attachments, and useful programs on a website. Unlike viruses and worms, trojan horses cannot replicate themselves; nevertheless, they can be extremely damaging. They can give a hacker control of your computer, delete files, infect files with viruses, and many other malicious features.

Rootkits
Rootkits are programs that hide in your computer and allow hackers to control it completely from a far location. Once installed, it gives hackers administrative control like changing settings, executing programs, accessing files, etc. Rootkits are very complex and sophisticated, thereby making it difficult to locate the hacker. Many times, hackers use rootkits to control a computer and launch other Internet attacks from that computer so its harder to find the malicious hacker.

If you believe your computer may be infected with some type of malware, please check for a few common symptoms, such as:

• Slow Operating System
• Corrupted files
• Less available memory than expected
• The Operating System does not start
• ...and many more! 

Now I know all these different types of threats can be overwhelming and very intimidating, however, you can protect yourself from these attacks as much as possible by downloading anti-viruses and setting up a firewall. These two safeguards are essential for protecting your computer, nonetheless, you must make sure to update them as the number of malware programs sharply increase monthly.

Anti-Viruses
Anti-viruses protect computers against malware by identifying "signatures" that viruses have. It scans for programs that try to alter the boot program, the OS, or any other programs. Once identified, it will remove it and give the user a report of the virus being removed. Anti-viruses have the option of running on "real-time" or "on-access" (meaning its constantly scanning). There are many different anti-viruses on the web, some are free and some require a fee. As a matter of fact, UF students can download the popular program McAfee for FREE from the Software Licensing Services.

Here's a snapshot of the Norton Symantec Anti-Virus I have installed on my MacBook:

Image provided by Albert Lopez, 2011.

Firewalls
A firewall is a utility program that protects a computer and its files from unauthorized intrusions by constantly monitoring all transmissions between the computer and the Internet. It specifically monitors everything going in and out of your PC's network card; it will block unauthorized access while hiding your PC from view on the Internet. It is very important that users set up a firewall even if its for personal use because hackers can access important data stored in a system. Moreover, many businesses use firewalls to keep their networks safe from outside intruders, and to protect sensitive information from their own employees. Both operating systems, Windows and Macintosh, include personal firewalls in their new computers. However, some users feel that they need more complex firewalls and go ahead and purchase such firewall programs from the market. My computer came equipped with a Mac OS X Firewall, as you can see in the snapshot below:

Image provided by Albert Lopez, 2011.

As you may know by now, the Internet can be a very risky place if you do not take the right steps to protect yourself and your computer files from cyber attacks. Becoming aware of such threats, downloading anti-malware programs, and keeping an eye out for the websites you visit, will certainly help you "surf the web" with minimal risks. I really hope this tutorial blog informed you about the different types of malware and what you can do to keep your computer safe from intruders.
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Useful References/Resources:
-http://www.software.ufl.edu/alphabetical_student.html
-http://www.opensec.org/internet-security/top-5-internet-security-threats
-http://www.microsoft.com/security/pc-security/protect-pc.aspx
-Shelly, Gary & Vemaat, Misty. Discovering Computers 2010. Boston, MA: Cengage Learning, 2010. Pp556-561.

Secure Email Project

Before starting the project, I really thought it was going to be more difficult--especially since I had no clue how to encrypt messages. However, the instructions helped a lot and I was able to complete it without many obstacles.

Here are the screenshots of my Thunderbird Inbox and Dr. Means' replies:

Images taken by Albert Lopez.

Article Link: http://searchfinancialsecurity.techtarget.com/news/1349375/Wells-Fargo-deploys-Voltage-for-secure-email

Article Summary:

Email security should be a main concern for most businesses—especially financial institutions holding sensitive information. Wells Fargo & Company has certainly made security a priority. An article published by Security Magazine talks about how the company has deployed Voltage Security’s SecureMail. When Wells Fargo began to look for a new security system, user experience was really important because not all customers are technology savvy. One of the benefits of SecureMail is that users do not need to download anything to access it; however, it does require users to use another server to identify information (such as an email address) that will unlock the message.

SecureMail has saved Wells Fargo time and money in sending confidential documents to customers and employees. As a matter of fact, about 20,000 employees and customers were using the program in 2009—this number has only increased since then.  Furthermore, It is believed that Wells Fargo will significantly broaden its deployment to approximately 175,000 users! Overall, I believe that Wells Fargo has taken an important step that will surely attract customers concerned with confidentiality and email security. It is vital that many other businesses do the same, especially since identity theft has become a growing issue. 

Extra Credit: Creating an Avatar

Creating my avatar fun and a lot easier than I thought. To make it, I used the website Doppelme. However, this was the 3rd website I tried to use. I first used Meez and IMVU, but I found them to be fairly difficult to use and did not have as many avatar options as Doppelme. I really enjoyed the Doppelme website because it was relatively quick to make an avatar and the site was very user-friendly.

Doppelme offered a variety of skin tones, expressions, hair style/color, eyewear, hats, clothes, shoes, and accessories. By having such a wide variety of options, the user can explore many different combinations and choose the one that best resembles them. It was very easy for me to find the right features that best portray me, such as the black hair, brown eyes, tan skin, and clothing style. Overall, I really enjoyed creating my avatar and learned about many of these websites in the process. I will sure use the website for different avatars I will make in the future.

Tutorial 3: Types of Multimedia on the Web

With more one billion users of the Internet today, the Web has expanded a long way since the formation of it in 1969.  In addition to its size increase, the Internet has also changed in the way websites present their information.  Once limited to only text, the Internet has expanded to also include graphics, animation, audio, video and/or video reality. The use of two or more types of this media is referred to as multimedia.  Most Web pages today include the use of multimedia as often it enhances the information provided on the page.  In this blog, I will introduce the many types of multimedia including: graphics, animation, audio, video and virtual reality.

Graphics

This digital photo was taken by Albert Lopez.
Like most digital photos the graphic was saved in the file
form JPEG.

Graphical images are popular to use on websites as they display non-text information such as images, graphs, drawings and photos in a digital format.  Often accompanying text, the use of graphics is a way to provide additional messages not included in the text. If you chose to upload graphics to your Blog or Social Networking page, you would notice that you're images have some scrambled letters following the title of your image.  This is the code for the type of format the image was saved as.  The Web contains a wide array of graphics in many different formats, but most often, graphics will be in JPEG, GIF, or PNG format. Different formats allow for a graphic to vary in size and image quality but often there is a trade-off between the two.  JPEG is one of the most popular because although it compresses the image to reduce it's file size, the image quality is not compromised in the process. A JPEG format is often best used for digital photos. Other graphic formats found on the web includes; BMP and TIFF.  Specific graphics are easily searchable on the web through search engines such a Yahoo! and Google. Searches for images appear as 'thumbnails' or icons of the image, but when clicked on can be brought to it's original size.

Animation
Another way to make a Web page more appealing to the eye is through the addition of animation.  Animation is often a display of concurrent still images to create the illusion of motion.  Much like a flip-book the images move quickly to appear as if there is movement on the screen. Such movement can be used to draw attention to a region of the page such as an animated title or a ticker to show a countdown.    Animation is usually seen in Web-based games.

This animation was created by Albert Lopez using www.crazyprofile.com/text_animation/

Audio
The multimedia listed above can also be used in conjunction with audio. Web based audio includes but is not limited to music, voice-overs or any other type of sounds in digital format.  Audio files can be added to Web pages through simple download of individual files to the site.  After the media file is downloaded, a software player such as iTunes, RealPlayer or Windows Media Player is needed to play the file.  Audio files also come in different formats to adjust file size and/or sound quality and again a trade-off exists between the two. Some common audio web formats are AAC, WAV, WMA and MP3. Audio files have become very popular on Web sites and can help to create an ambiance for a website when playing in the background.  For example, if a hotel wanted to create a calm setting for it's website to reflect the peaceful feel of the hotel, it could play serene music in the background. Sites that just play audio tracks for listening entertainment have also become very popular recently such as Pandora and Grooveshark.  These websites use streaming audio or an audio file that can be played as it is being downloaded to it's distribute music in the form of online radio. Here's an example of online audio files.
Cymbals:

This audio file was created by Albert Lopez.  This is an example of a MP3 formatted file using a Public Domain audio file of cymbals playing.

Video
Another type of multimedia available is video in the form of video clips or live video.  Video uploading sites such as YouTube allow for video distribution, sharing and viewing of videos across the Internet.  Videos can be seen either through a link on a website, through a video distributing site such as YouTube or can be embedded directly on the website.  Video clips can enhance a site as it provides information in a much different way and somewhat interactively. Clips can vary from movies, TV shows, video diaries, tutorials, advertisements etc. As the internet has increased  the number of it's audience over the past few decades, more businesses have taken advantage of the Internet as an outlet for advertisements.  As more of these advertisements come in video format, video will be seen in more and more websites that originally only included text. Because these files are often very large and therefore like images and audio they need to be compressed for less download time. Here's an example of an online video.

This is a video created by Albert Lopez.  It is uploaded through blogger.com and recorded through my Macbook. 

Virtual Reality

Lastly, Virtual Reality or VR is a type of media that allows for virtual activity in a computer-simulated environment that seems like a 3-D space.  Users can use the space interactively in the VR world by moving through a display of 3-D images.  Applications of the VR world can be used for entertainment (games), education (models of molecules, organisms), or as a way to showcase any structure (as in architecture etc). The website, www.secondlife.com is a great example of a VR for entertainment.

This image was printscreened by Albert Lopez.
Second Life as shown above, is an example of a Virtual Reality.

The Web has come a long way from when text was its only type of media.  Today, websites include a multitude of media. In this blog, I have showed you five types of media; graphics, animation, audio, video and virtual reality.  I hope that you have learned a lot about the many types of media available on the Web today!


Works Cited

"Cymbals." Public domain: free downloading & streaming. Web. 25 Mar 2011. <http://www.archive.org/details/cymbals_360>.

Lopez, Albert, Dir. Video Example. Blogger: 2011, Film.

Lopez, Albert, Photographer. Beach graphic example. 2011. Digital Photo.


Shelly, Gary. Discovering Computers 2010. Boston, MA: Course Technology Cengage Learning, 2010. 92-96. Print.

"Text Animation." Myspace text animation, piczo text animation, html code. Web. 25 Mar 2011. <http://www.crazyprofile.com/text_animation/>.

"Virtual Reality Example." Second Life. Web. 26 Mar 2011. <http://secondlife.com/whatis/?lang=en-US#Meet_People>. Printscreened by Albert Lopez

Database Project: Using MS Access

Before working on this project, I had never used Microsoft Access. I have heard so many great things about it in the past, but never actually used it. After watching the Access videos, practicing activities, and completing this project, I now see why so many businesses and people give it such great reviews!

One of the most important features I learned about Access was creating reports. I find this feature to be very helpful when presenting co-workers with data at meetings. Thanks to reports Access creates, data can easily be analyzed when grouping and sorting out data. When working on the project, I was able to quickly look at all the customers in a specific city, and see the most recently departed first. Another really important element that I learned to use was queries. Queries can be extremely helpful when you want to limit the amount of data in a table (like we did in the project). Moreover, queries allow the user to do so many different things including create, retrieve, update, and delete large amounts of records.  I found it very useful using queries to filter data through different fields. In turn, using queries are very advantageous when wanting to create a report with limited data later on.  

Overall, I learned so many other features—especially since I had never used the program—but it would take many more paragraphs to talk about them all. Most importantly, I learned how great the program is, its features, and how I would apply them in the business world and my future career.

I believe that adding payment information in the “New Members Form” can be useful when members fill out their forms. A text box can be integrated that will tell the gym owner what type of fitness plan they would like to sign up for. The form will copy this information and update it on the “members” table. Another way to enhance the functionality of the database is to add a field that shows the next payment due dates for each member. This can be useful to owners when sending reminders to their members, and can be useful when creating reports for finance meetings.

Web 2.0 Presentation: Keep America Beautiful

Link to Web 2.0 Presentation: http://www.youtube.com/watch?v=e8XBxhUyNcs

Creating this Web 2.0 Presentation taught me a lot about very useful technology and resources that I have not used before--such as Camtasia and a few PowerPoint features. Critiquing my own presentation was both interesting and useful. I learned a lot about my presentation and myself as a presenter. In regards to my presentation, I strongly believe it had logical flow and sequence of content. I first set up environmental problems that led up to non-profit organization I wanted to focus on, which was "Keep America Beautiful". However, I do think I could have added more details on a few slides--however, I did not want to put too much information and bore my audience. In addition, I believe I anticipated questions and answered them in the right place. I provided useful information, referred to a few questions that the audience probably had, and I answered them right after that.

In my presentation, the attention grabber was the shocking fact provided by a reliable website discussing Recycling and Waste. The attention grabber was the fact that the US is the #1 trash-producing country in the world, in other words, about 5% of the world's population makes up 40% of the world's garbage. In my opinion, that is a eye-opening fact that has made me more conscientious about the amount of waste I produce. I certainly asked a few questions that probably go the audience thinking more about the topic, such as "who does this affect?", and "How can I help this organization?". I feel that such questions allow the audience to reflect on the topic's issues, and thereby be persuaded to donate to the organization. On the other hand, I do believe I could have asked more profound questions that sparked the audience's curiosity a little more. Moreover, I made sure to set the context with a concise explanation and to be clear about the presentation's purpose. Although what I was trying to share was pretty clear, I think I should have done a better job at validating some claims.

Furthermore, I stayed away from errors and inconsistencies, as well as typos within my slides. Unfortunately though, there were a couple of small speech errors in the narration; I tried to avoid them as much as possible, but I had a hard time editing parts of the audio. In regards to the slides design, I tried to keep my slides simple to avoid clutter and ensure readability. I made sure my font was large enough to read and I used good font colors that stand out such as black, orange, and blue. Apart from reading a few facts from the slides, I explained a few pictures, and provided additional information relevant to what I wanted to show. I thought this was important because I did not want to put too much information in each slide and I tried to avoid signal-to-noise ratio from bullets and pictures. After completing my project, I criticized another student's presentation to help me realize how I could improve my presentations in the future. I ended up learning a lot about my peers, their designs, narrations, as well as the different types of media they used. I also learned about very interesting organizations, and great techniques on how to persuade someone to donate.  

Overall, I found this project to be highly interesting and useful for my career in the future. I became a bit more familiar with Youtube and some of their features as I uploaded the presentation. Most importantly, I learned how to use Camtasia for macs. Before this project, I was not familiar with any programs that recorded presentations from the computer screen; I learned a significant amount about how to use Camtasia, its features—and in general, how to improve my presentations. I strongly believe that learning how to use such programs will improve the quality of the business plans I will present throughout my career. This knowledge will also be very useful in the marketing aspect of business. Marketing companies can use these powerful resources to persuade the consumer more efficiently and effectively. I will certainly use what I’ve learned from this project in the future when I start my own business. Finally, I think learning how to use such resources is essential in this very competitive business environment. Globalization and information technology are becoming significant factors in the continued progression of economic marketing schemes. Therefore, by applying these new skills and using such resources, I will definitely have a competitive advantage in my career.  

Tutorial 2: Excel Trend-lines and Charts

Becoming proficient in Excel has become almost mandatory to enter the business arena.  Excel is an excellent tool to create and analyze spreadsheets, charts and graphs.  In a growing and fast-paced technological world, it has become fundamental to be able to utilize this program in your professional life and should be a key element in your resume. I believe it is both important and useful to learn how to create charts and graphs, so in my second tutorial I will introduce the concepts of Excel graphs and trend-lines, and show you how create a graph, in particular a Scatter Plot graph.

Trend-Lines
The linear trend line in Excel is nothing more than the regression line you've learned in school. This trend line approximates how the expected value for y changes at different values of x. Here's an example of a regression line:    y = a +bx

In a scatterplot, a residual is the vertical distance between the data point and the trend line. The smaller the distance, the better the prediction. The trend line has a smaller sum of squared residuals than any other line, that is why it is also known as the least squares line.

One of the most important skills you can have in the business world is being able to create a graph and show its trend line. I will now show you how to create a graph, and add its trend-line.
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To begin creating your first chart, first open a new workbook and enter your desired data.  The data used in the example will graph fictional monthly utility costs of an apartment.  The data is fake and the images will be a compilation of my own 'print-screens.' Keep in mind I used Excel 2004 for Mac, so these instructions may differ for a more recent version.

1.  Enter your desired data (Entered below are the months beginning with when I began collecting fake data and it's corresponding utility charge.)  I have entered my data in the form of 'Month 1, Month 2' etc.

Also when filling in this information be sure to add in your data correctly, if not the data presented in the graph may not be representative.  Notice in the image above I have matched each utility charge to its correct numerical month.

2.  Highlight the information you wish to include in the chart.  I have highlighted the month and then that month's utility charge.  Do this by holding down on the first-most left cell of which you wish to include, and drag this down to include all the data you wish to include.

Notice that I have not included the headers 'Month' and 'Utility charge' because I do not wish this to be in my data set.

3.  Click on Insert. A menu will drop-down, and follow it down until you find Chart.

4.  Chart Wizard will bring up a list of charts that may be suitable for your data.  Scroll down each type of chart and find one that best fits your data.  I believe a scatter plot will best represent my data so I clicked on XY (Scatter.)  To select, click on the Chart Type's title and highlight it, than click the Next button.

5.  The Next button should bring up the Chart Source Data dialog box which will tell the Excel program which data to use.  At the top of this box there should be two tabs Data Range tab and Series tab.  Click on the ladder, Series tab.  You may feel free to explore the Data Range tab but listed below will only include the Series Guidelines.

6.  Check that the data match your X and Y values.  

Excel will automatically assume which values to be on your X and Y.  To make sure this is correct look to see that the information in the X Values box correspond to that on your spreadsheet.  For example: In my data set, my X values will have the code:

The letters A in this code correspond to the information in column A.  Notice that also in the code is 2 and 13.  This will tell the program that you wish to include data points from cells 2-13.  This code altogether tells the program to include all cells from column A and from cell rows 2-13.  Make sure this 'code' corresponds you're X and Y values to the data in your spreadsheet.

7. Click Next to continue to your dialog box Chart Options.  Give your graph a Title, and be sure to label your X and Y axis's and include the units to each. Above this are tabs to customize your graphs.  Feel free to play around with these tabs but descriptions for other variations will not be provided in the scope of this guildelines.

8. Click Next once you are happy with the specifications of your graph and it will lead you to a new dialog box.  If you wish to include your graph with your spread sheet click As object in bubble.  This will include your graph in the spread sheet you created.  You can also create this graph to appear in a new sheet.  I will include it with my spread sheet.  Click Finish to complete your graph.

9. Your chart should now appear on your spreadsheet.

10. If you are discontent with the appearance of your graph you may change it by clicking on one of the points.  All of the points should now be highlighted.  A dialog box Format Data Series box should appear.  Edit the preferences of your graph here such as the Background, Foreground and Bullet Preferences.  Once you have finish this, again click OK to finish.

11.  Finally to add a trend line, right click any point on the graph.  A drop down menu will appear, scroll down to Add Trend line.

12. A dialog box will appear and a list of types of trend lines will appear. There are two tabs, Type and Options.  Under the Type tab choose which graph type you would like.  Feel free to explore the options tab as well.  For this graph I chose to include a Linear trend line.  Click OK to finish.

This tutorial was created to help you excel at Excel Charts.  I hope you have learned a lot and that these diagrams have helped you.

Source: All images were created by me. Copyright 2011 Albert Lopez.

Excel Project

For the Excel Project in this course, we were given the heart rates of 500 fitness center members and were asked to perform specific tasks on Excel. The heart rates were measured  at 1 minute intervals throughout the 15 minute workout, and through the 5 minute cooldown.

First, I was asked to reformat a few items to make the worksheet look more organized. I then used the “Freeze Panes” capability to lock in Rows 1 and 2. I was familiar with this feature, but did not know how to freeze more than one row until I watched the Excel videos. After this, I was asked to add a new column that estimated the maximum heart rate for each member, and a column that calculated the target heart rate. However, the latter column required the use of absolute referencing. When using Excel in the past, I have needed to use this feature but did not have the slightest clue on how to use it. Now I know that if I need to reference a specific cell in a formula, all I have to do is put a “$” in front of the column and row (Ex: $C$6). This is something so simple, yet USEFUL! Next, I used the maximum formula to find out the highest heart rate achieved by each member. Afterward, I had to use an “If” statement formula to determine whether each member achieved their target heart rate. Before doing this project, I had no idea how to write “If” statements on Excel. I think acquiring this skill is very important for analyzing data and for decision-making, and I am very happy to have learned this feature. Next, came a few simple tasks such as calculating the percentage increase in heart rate, creating some headers and footers, and changing a few printing options. The second part of the project required some data analysis using Pivot Tables. One of the tables organized the average percent increase in heart rate by gender and age group. Here’s a screen shot of the pivot table I created:

Overall, I found this project to be very entertaining, useful, and informative. It was a great way to learn and apply all the Excel fundamentals. I learned quite a lot about different Excel features, and have acquired many skills needed in the business environment. Some of these new skills I acquired include using relative and absolute referencing, creating “if” formulas, using freeze panes, making pivot tables, and analyzing large amounts of data. I believe all of these skills will certainly be helpful in my future business career.

Tutorial 1: Windows XP Disk Scan and Defragmentation for Beginners

Has your computer been slowing down? Want to increase its performance? Then you may want to try 2 easy options--Disk Scan and Defragmentation. They are 2 great disk utilities that will not only improve your computer's performance or reorganize your files, but it will also correct many disk errors...for FREE! Yes, it is completely Free because it has already been installed on your Windows XP computer. If this is your first time running these programs on your computer, get ready to be surprised at the difference in speed. We will discuss some background information about these utilities and the step-by-step procedures to perform these tasks.

Disk Scan

Using the Disk Scan feature is very important to keep your computer up and running, it is a very essential part of computer maintenance. By running a disk scan, the OS utility feature checks the hard drive for errors and bad sections. If any errors are found, it will attempt to fix them. This will allow your computer to run efficiently and error free. Follow these steps to start scanning for errors:

1. Click on My Computer located on the desktop.

2. Right-click on the disk you would like to scan, and select Properties. The hard drive properties window should come up.

3. Pick the Tools tab. To begin Disk Scan, click on Check Now...

Picture was provided by Tech Ease (See Reference1).

4. The "check disk options" will appear. It is preferable to check both options:

• Automatically fix file system errors
• Scan for and attempt recovery of bad sectors

5. Click Start. Another window will appear asking to schedule the disk check next time you restart Windows, click Yes.


6. Close all the windows and programs, and restart your computer. The Disk Scan will automatically begin.


Defragmentation

Before you perform this task, you may want to know what Fragmentation is. Very briefly, disk fragmentation occurs over time when you use the disk, create, modify, and delete files. The disk will naturally try to place all the files in contiguous spaces, but there comes a certain point that the it must place parts of a file in noncontiguous clusters. This of course slows down your computer, as it takes the disk a little longer to locate all clusters for each file. The diagram below shows how the disk clusters look before defragmentation.

Picture was provided by PC Guide (See reference 2)

As you can see, File F takes up 4 clusters, but was placed in empty spaces throughout the disk and therefore makes it noncontiguous. Here are the following steps to fix this problem as much as possible and therefore increase your computer's performance:

1. Click on My Computer located on the desktop.

2. Right-click on the disk you would like to defragment, and select Properties. The hard drive properties window should come up.

3. Pick on the Tools Tab, Select Defragment Now...

4. The Disk Defragmenter program will open up.

5. Select the Defragment button. The defragmentation process will begin; it will analyze and reorganize your files. Over time, it will take the previously heavily fragmented disk and make it more organized.

Picture was provided by the University of Iowa (See Reference 3)

Hope these steps and diagrams helped you. If you need any more information regarding Windows XP Defragmentation, please visit this article on the Microsoft Support page. According to this course's lectures, Microsoft suggests that defragmenting hard drives should be part of a "frequent and regular maintenance program to maintain the optimum performance..." 

**In addition, some videos regarding Disk Scan and Disk Defragmentation have been attached for your reference; they are very helpful in showing you the steps to using these programs as well as providing some basic facts:

VIDEO REGARDING DISK SCAN

VIDEO REGARDING DISK DEFRAGMENTATION

**Both videos were provided by YouTube**

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References:

1) "How do I scan my hard drive for errors?." Tech-Ease. University of South Florida and the Florida Department of Education, 2010. Web. 25 Jan 2011. <http://etc.usf.edu/techease/win/hardware/how-do-i-scan-my-hard-drive-for-errors/>.

2) Kozierok, Charles. "Fragmentation and Defragmentation." The PC Guide. The PC Guide, 17 April 2001. Web. 29 Jan 2011. <http://www.pcguide.com/ref/hdd/file/clustFragmentation-c.html>.

3) "How to Defragment your Hard Drive (Windows XP)."IT Services at the University of Iowa. The University of Iowa, n.d. Web. 28 Jan 2011. <http://helpdesk.its.uiowa.edu/windows/instructions/defrag.htm>.

4) "Perform a Scan-Disk Function using Windows XP."YouTube. Web. 27 Jan 2011. <http://www.youtube.com/watch?v=91SBw9Fkmsw>.

5) "How To Defrag Your Windows XP Hard Drive."YouTube. Web. 28 Jan 2011. <http://www.youtube.com/watch?v=TsYt821jGQ8>.