US Advanced Technology

What’s That File?
An Introduction to File Extensions

In an effort to be “user-friendly,” Windows (and perhaps some other operating systems) hides the most important part of a file name from new computer users: the extension. Okay – we’re assuming that the reasoning behind hiding extensions is a “user-friendly” one because we just can’t come up with any other reason for hiding them. No harm could ever come from seeing an extension, but plenty could be learned from it. Fortunately you have this article to guide you through some of the most common extensions that you’ll run into.

But before you can see file extensions, you need to turn them on. From Windows Explorer, click on the “Tools” menu, and select “File Options.” Click the “View” tab and then uncheck the box next to “Hide file extensions for known file types.” Click “OK” and you’ll notice that the files in Windows Explorer show a dot and group of three letters after their names. That dot and group of three letters is known as an “extension,” and the extension explains what kind of file it is.

A file could be a plain text file, an image, a sound, a video, or program. But without seeing the extension, you wouldn’t know it unless you double-clicked on it. The following list defines some of the most common extensions that you’ll find on your computer.

.au – This extension indicates a sound file. Most sound players will load up and play this kind of file.

.art – This extension indicates an image file that was compressed with AOL (America Online) technology. Both Internet Explorer and the AOL service software can display this kind of file, however if you don’t have AOL installed on your system, Internet Explorer will display it.

.avi – This extension indicates a video file playable by most multimedia viewers including Microsoft’s Media Player.

.bmp – This extension indicates another image file that might have originated from Windows Paint program.

.dll – This extension indicates a Dynamic Link Library which may contain additional programming code for software. Many different programs often share Dynamic Link Libraries and you’ll find a bunch of them in the Windows/System directory (but don’t ever delete them)!

.exe – This extension indicates a program or an application like Microsoft Word, Internet Explorer, or Outlook Express. Use extreme caution when downloading .exe files from the Internet since malicious programmers like to hide viruses in these types of files.

.gif – This extension indicates another image file and it stands for “Graphics Interchange Format.” .Gif files are often smaller than .bmp files (described earlier) and they’re commonly found on Internet web pages.

.jpg – This extension indicates yet another image file and it stands for “Joint Photographers Experts Group.” Like the .gif file, it’s commonly found on Internet web pages, however it’s much smaller than both the .gif image and the .bmp image.

.mid – This extension indicates a sound file created with a Musical Instrument Digital Interface. Windows Media Player will open and run these files, however they don’t sound like normal .wav or .mp3 files (described later). .Mid files are designed to product synthetic sounds using a computer’s sound card.

.mp3 – This extension indicates a sound file that authentically reproduces voice and/or music. Windows Media Player will open and run this kind of file.

.scr – This extension indicates a screen saver file.

.sit – This extension indicates a Macintosh archive StuffIt file. They will not open on a Windows system without a special utility.

.ttf – This extension indicates a font especially designed for use on a Windows system. It stands for “True Type Font.”

.txt – This extension indicates a plain text file that can be opened with Notepad.

.wav – This extension indicates a sound file that like the .mp3 file, can be opened with Windows Media Player or Windows Sound Recorder. .Wav files are much larger than .mp3 files.

.zip – This extension indicates a Windows archive WinZip file. They will not open on a Macintosh system without a special utility.

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Viruses
What They Are And One Reason Why People Make Them

Over recent years, computers have become synonymous with viruses and viruses don’t show any signs of disappearing any time soon. In recent news, LiveScience.com reported that “Before the month is even done, April has set a record for virus e-mails.”1 In the past, we would be comfortable in telling new computer users not to worry about viruses and that catching a computer virus is rare. Today, that would be some of the worst advice we could give anyone. As reported in countless news reports, computer viruses are rampant and they’re extremely worrisome. This article will describe what viruses are and then point you in the direction of some rather unique protection and prevention.

In short, a computer virus is a software program designed to destroy or steal data. It attacks computers via distribution – often unknowingly – through email attachments, software downloads, and even some types of advanced web scripting. Viruses that destroy data are known as Trojan horses, viruses that explode their attacks are called bombs, and viruses that duplicate themselves are called worms. Some viruses are a combination of each, however they can be further identified according to where they’re located on a computer.

A virus originating from the boot sector of a computer is a boot-sector virus and this nasty devil does its dirty work the moment a computer is turned on. A virus that attaches itself to (infects) other programs is a file virus and activates the moment that an infected program starts. File viruses may also be referred to as parasitic viruses, however should a virus work from both the boot-sector and from an infected program, the virus is then known as a multipartite virus.

Why viruses exist remains a mystery, however we had privy access to the mind behind a virus programmer who explained his motivation behind his destructive inclinations. Apparently, this person had a deep grudge against a popular online service which shall remain unnamed. In this hacker’s mind, the online service failed to do a quality job in protecting children from online smut and as retaliation, he created and distributed a virus to as many file libraries of this service as he could. His intentions were to disable the computers of the online service’s users so much that they wouldn’t be able to connect for days. In his mind, the loss of connection meant loss of revenue for the online service.

Although the malicious code that this person generated may have worked for a small percentage of users, sufficed to say, the online service continued on and still exists today. Despite his motivation or intention, his efforts were null.

We wouldn’t be surprised to learn if other motivations behind spreading viruses were similar to this person’s, but that doesn’t justify the damage that viruses do. Innocent people become pawns for the evil plans of others who’ve convinced themselves they’re doing the “right” thing.

To protect a computer from getting a virus, or clean a virus from a computer system once infected requires the use of an antivirus utility. But may be something else we can do. Perhaps we could make an effort to educate the people who want put viruses into the public about ways to display dissatisfaction with a service or product that don’t involve harming innocent parties. In doing so, we just might reduce the number of virus news stories and protect our own investments at the same time.

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1 Source: http:// news.yahoo.com/s/livescience/20070426/sc_livescience/recordsettingspameffortturnscomputersintozombies

Every new computer that’s brought home from the store has an operating system installed onto it. But what most new computer users don’t realize, is that without an operating system, that computer would be a simple shell of possibilities. A powered computer lacking an operating system wouldn’t display anything more than a bunch of confusing text messages that describe the computer’s boot process. At the very end of this process, the computer looks for an operating system and if not found, it will prompt the user to tell it where it is.

Earlier computers didn’t have an operating system and if you have experience with the computers of the early eighties, you’ll remember that most to them didn’t even have a hard drive! These old computers booted an MS-DOS type operating system from drivers stored onto a floppy disk, and in order to use a program, users would remove the boot floppy and then insert a new floppy that contained the program. The floppy not only stored the program

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If you’ve spent any lengthy amount of time on the Internet, you’ve probably heard of open source software but might not have fully understood what it is and why it even exists. This article will describe this recent phenomenon and describe some of its benefits for the software using community.

In a nutshell, open source software is software made by everyone – for everyone. The hopes behind its development is that through its open access, it will evolve into something that represents the true desires of computer users. Through a wide network of user involvement, the software in question is enhanced and debugged without costs or administrative politics.

Traditionally, software is developed behind closed doors. A team of professional coders build it but the community at large isn’t part of its conception. It’s costly to produce and as you can probably guess, that cost is passed on to the end user: the consumer. Open source software on the other hand is free. Free to download, free to install, free to use, free to modify, and free to share.

Started over twenty years ago, it’s a phenomenon that is gaining in both popularity and exposure. In its first conception, open source gave birth to the World Wide Web as we know it today. The Internet as a whole is the result of free permission to access the web, use the web, contribute to the web, and share the web with others. But it certainly hasn’t stopped there. In the not too distant past, Netscape converted its once commercial version of its Navigator web browser to open source. And today, open source is venturing into the commercial realm as well.

At first thought, the idea of open source may sound just plain crazy to those who earn a living from software development. But the facts point to a different prediction. Open source software puts companies in a terrific position to re-brand and re-position themselves in a market that they may have not been able to reach before. In the business world, open source is all about image and when consumers witness corporations contributing (instead of selling) to the buying public, they gain big favor in the eyes of their users (plus tremendous opportunities to sell other items).

Inviting the public inside a product’s development builds community and trust. It also sets the platform for increased reliability. Fans of open source programs are adamant about reliable software and highly criticize commercialized versions for being buggy and error-prone. Avid fans even proclaim commercialism is the cause of shoddy software.

Another benefit that open source brings to light is the speed at which its products are developed, enhanced, supported and distributed. This is because the people who regularly contribute to an open source product do so for unmotivated reasons (other than perhaps to feed the ego.) They’re highly talented, they’re available, and they care. Bringing money into any project can almost mean instant death. It can kill motivation, desire, and a true willingness to create a good product. In a commercial setting, participants work for a paycheck rather than for the product. And this is what puts open source projects far ahead of its monetized competition.

As a software user, this means you can contribute to an open source project as well, and help to develop it into a product that reflects your direct preferences. You aren’t “stuck” using open source software the way you would be stuck using an expensive word processor or database. You have the same access to open source software as its programmers have and in essence, you are your own customer!

Perhaps at this point you’re wondering where you can get in on this wonderful opportunity. There are plenty of open source opportunities sprinkled across the Internet and they can be easily found though any search engine. Google “open source project” and you’ll be sure to find more resources than you can shake a stick at!

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Networking Home Computers
Increasing Productivity With the Whole Family

Have you ever thought about networking your computers at home? If you have a small collection of computers around the house (and a small collection of computer users), you can connect each one of those computers to one another and share data, software, and hardware including a single Internet connection. There are many creative uses for home networking, however it’s an ideal situation when upgrading each computer to the same capability is financially out of the question. On a home network, each computer has access to the equipment of the better machine in the group as if that equipment were their own.

Connecting computers with either an Ethernet cable or a Wireless connection can create a home network. The easiest and cheapest method uses an Ethernet connection, which requires a series of network cards, a cable for each computer, and a router. The network card is similar to the old modems we used in the past to connect to the Internet, however in a home network, it’s used to communicate with every computer that’s connected to it.

You’ll want to first, select the computers that will connect to each other and then install the network cards inside each of them. Then you’ll connect a cable to each computer that will communicate with the server. These cables won’t connect to the server directly. Instead, they’ll connect to the router. To enable Internet access for each computer, this router will need to connect with a modem of the host machine.

Once the hardware is set up correctly (you’ll need to read the instruction manual of your equipment for details), you can then setup the network from Windows on each machine. Within Windows, you can set up a home network similar to the way that you set up an Internet connection. Only this time, you’ll set up a LAN (Local Area Network) connection.

Windows should walk you through setting up a LAN after starting the computer and once complete, you can begin to connect one of your machines to the network. You can do this through Internet Explorer by typing in the address and password required to access the router (the address and password required to access the router will be in the router manual).

Connected to the network, each computer can send files back and forth, open programs on a remote computer, play the sound files and videos located on another computer, and share a single Internet account to browse the web, download files, or chat with someone in an entirely different country. If a single printer is available on only one computer in the network, every connected PC can send documents to it and print them out. Kids will enjoy the ability to play multi-player games and adults will enjoy the ability to blast a single message to everyone at once or maintain a group schedule.

Since we’re describing a home network that will connect to the Internet, you’re strongly advised to install a protective firewall program to thwart Internet viruses, worms, or other damaging spyware code. Firewalls prevent – but they don’t repair. Only anti-virus and anti-spyware programs can reverse damage. So you should install a firewall on the computer that grants access to the computer, and then install an anti-virus and anti-spyware program on each of the remaining computers in the network.

If you have files that shouldn’t be shared (bank statements, credit card information, etc.), you can restrict their access in one of several ways. You can put them in a new folder and then remove the “read” permissions for that folder. Or you can specify who can (and who cannot) access specific files with a password from within Windows Control Panel.

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Cheap and Fast Software
An Introduction to Shareware

Visit any computer store today and you’ll find what seems like miles and miles of software on sale. Certainly enticing buys, there are a few problems with buying software off the shelves. On the shelf, software – otherwise known as “commercial software” – can be expensive, and incompatible, and outdated when compared to what’s available online. Fortunately, there’s an alternative to commercial software and although it isn’t new, it’s one of the most under-exploited opportunities in the computer industry.

We’re talking about shareware – software that you can try before buying.

Shareware has a long history and was rather popular in the days where BBS (bulletin board systems) reigned the online industry. It hasn’t gone anywhere, but its competition with commercial software is fierce – so fierce that it tends to fall on the back burner among new computer users. This is unfortunate because shareware has so many advantages over commercial software.

One of those advantages is its cost. On the whole, shareware is generally cheaper than commercial software. But don’t misinterpret the cost. With shareware, cheap does not equal low-quality and there are plenty of examples that prove shareware often outperforms the quality of commercial software time and time again. How much savings are we talking about? You could purchase a quality word processor, spreadsheet, database program, or system utility anywhere from a mere $15 to under a hundred. This is almost unheard of in stores like Best Buy, Circuit City, or Egghead, yet the shareware programs offered within this price range rival even Microsoft’s Office suite.

Another advantage that shareware has over commercial software is its compatibility. We’re not saying that shareware is compatible with all operating systems. What we’re saying is that since we can try shareware before paying for it, we can determine if the software is completely compatible with our systems first. In other words, we can discover whether the software performs the way we want them to and should anyone try to do the same with commercial software, they’ll be in for a big disappointment.

Commercial software policy doesn’t even allow for returns, let alone “borrowing” them to try them.

The last advantage that shareware has over commercial software (but certainly not the least) is its applicability. Plain and simple, shareware is the best bet when you want to keep on top of the latest release of a particular program. Sure, computer stores do their best to keep their inventory up to date, but when you can download version 5.6042 of a shareware program as opposed to buying a commercial 3.0 version from the local computer shop, there’s just no comparison.

Which brings up our next point. Just where does one get shareware? Shareware is all over the Internet and it’s really hard not to bump into it. The most popular places to find shareware is within thousands of download libraries, however the companies (and even independent programmers behind shareware) are increasingly offering shareware from their own websites. A simple Google or Yahoo search for a particular type of program will yield all sorts of results that point you toward items that you can try before you buy.

Be aware however, that because shareware is not commercial software, you may not experience a full program the way you would if you bought the software out of a box. Shareware may or may not be limited – meaning that some functions may not be available to you until the program is paid for. These limitations are often small and don’t interfere with the way its full version operations. They’re really just implemented as a way to prompt payment. Remember that shareware is not freeware. You shouldn’t try to use shareware as commercial software without paying for it.

About the only thing that’s similar between shareware and commercial software is the way in which they may be bought. With a credit card, you can be the new owner of your own software within minutes.

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