COMPUTER VIRUS

A computer virus is a computer program that can copy itself and infect a computer. The term "virus" is also commonly but erroneously used to refer to other types of malware, including but not limited to adware and spyware programs that do not have the reproductive ability. A true virus can spread from one computer to another (in some form of executable code) when its host is taken to the target computer; for instance because a user sent it over a network or the Internet, or carried it on a removable medium such as a floppy disk, CD, DVD, or USB drive.

Viruses can increase their chances of spreading to other computers by infecting files on a network file system or a file system that is accessed by another computer.

As stated above, the term "computer virus" is sometimes used as a catch-all phrase to include all types of malware, even those that do not have the reproductive ability. Malware includes computer viruses, computer worms, Trojan horses, most rootkits, spyware, dishonest adware and other malicious and unwanted software, including true viruses. Viruses are sometimes confused with worms and Trojan horses, which are technically different. A worm can exploit security vulnerabilities to spread itself automatically to other computers through networks, while a Trojan horse is a program that appears harmless but hides malicious functions. Worms and Trojan horses, like viruses, may harm a computer systems data or performance. Some viruses and other malware have symptoms noticeable to the computer user, but many are surreptitious or simply do nothing to call attention to themselves. Some viruses do nothing beyond reproducing

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Computer Maintenance Tips and Advice

It seems like just about everyone has a computer, but for the most part, relatively few understand much beyond on/off, open web, facebook, twitter, etc. I was once like that, maybe a little more knowledgeable. I gamed on my PC and could Google (or Yahoo back in the day) most issues I had. It is important to be able to resolve some basic issues on your own, but what Id like to cover here is a few tips on how to avoid having issues from the start.

Protect your Computer

Credit http://news.discovery.com/tech/first-human-infected-with-a-computer-virus.html

Anti virus software is extremely important. You dont need to spend $80 a year on Norton, but you should definitely purchase something. PCs are vulnerable to a multitude of attacks, whether from emails, websites, malicious programs, or direct hacking attempts. Having a good anti virus installed will remove a lot of headaches, and generally dont impact performance much if at all.

Theres some free anti virus programs out there like AVG and Avast! and Windows Security Essentials, theres also ones you pay for like Norton, McAfee, and F-Secure. I use the latter. If you are a student, chances are your school will provide either a free or a discounted anti virus program. If not, perhaps you can get a deal through work. Keep in mind that the free anti virus programs may need to be used together, with programs like Malwarebytes and Spybot.

List of Windows 7/Vista/XP security software

Keep Backups

The risk of losing everything on your computer is not huge. However, what if it were to happen? What if you lost all your home photos and videos? Maybe you have school work, or business work, on your PC. Its probably not worth risking.

One option you have is to use online backups. There are "cloud" services that offer online storage. You can always upload your photos to somewhere like photobucket, but its probably faster and easier to just maintain your own personal backups.

Info for Windows 7 users: Backup and Restore

Another great feature is Restore Points. These are backups of only critical items like your registry, so they arent huge files, and they save every time you install something new. In this way if you find suddenly your PC is acting weird, you can restore it to a point maybe a few days or a couple weeks earlier, when it was still fine.

Hard Drive Maintenance

At least on a monthly basis run a Disk Defrag program. Windows comes with one by default, but according to a fairly thorough benchmarker, MyDefrag appears to be one of the best. After you delete a few items of your computer, it will leave empty spots on your HDD. Eventually youll install something else, and pieces of it will get stored in all these different locations. This means accessing a fragmented file can take a long time, because instead of a fast sequential read, it will be more of a random read as the head needs to constantly move around to read each little piece of the file. Note that HDDs are built to run for millions of hours, a defrag operation isnt any worse than what happens when it is fragmented, and shouldnt impact HDD longevity. There is a sidenote: this is not applicable to Solid State Drives, which should never be defraged.

A great review on the Impact of Disk Fragmentation

Another important thing to do at least every few months is to run a scan disk. Once you set it, you will need to reboot and then it will scan your HDD after the intial boot screens. What scan disk does, is it looks for sector errors on the HDD and either recovers them or essentially "removes" them so that data isnt put into a bad sector. Sometimes a bad sector can cause a lot of stability issues. Scan Disk is found in your System Tools (Start Menu > Programs > Accessories > System Tools. Please be aware, if you start getting bad sectors, the problem usually will get worse and worse until your drive is completely useless. If this is the case, please go get a new HDD.

Clean your System

You should consider deleting and uninstalling anything you dont use regularily. If you have a huge amount of photos and videos, consider burning them to a DVD or external drive and free up HDD room. This can also help improve performance, as HDDs slow down the more full they are.

Windows registry is a vital part to a stable PC. It contains key values for every single thing installed on your PC, and then some. It is in many ways at the very core of your PCs performance and stability. Eventually, a registry will get full of clutter. I use a program called CCleaner to keep my registry free of junk. This program is also good for finding other clutter on the HDD, like temp files. You shouldnt clean your registry all the time, but even every other month is good. Keep in mind that this can cause issues, too, so please at the very least make sure youre backed up and also save the registry before cleaning (via the prompt).

You can also go into your System Tools and run the Disk Cleaner which can find some of the junk left over. For example if you install a Windows Service Pack, you might have a couple hundred megabytes occupied by a "ghost image". Essentially this is a redundant backup - you may wish to keep it for a couple weeks after updating to a service pack, but otherwise its just taking up space.

I would also suggest if you need to reinstall a program, do what you can to uninstall the old one/old version and remove it from your system. Sometimes left over traces of a program can really mess with a new install. With regards to graphics drivers, see yesterdays post.

Some programs, when uninstalled, like to leave traces outside of the registry - traces that use up sometimes precious hard drive space. You can manually hunt these down, typicall within the install location as well as in C:UsersyournameAppData or under C:ProgramData - both of these files are typically hidden. An easy way to find them is to run a search. Alternatively, a program like Revo Uninstaller can be extremely useful.

Clean your PC

Credit: i264.photobucket.com/albums/ii184/3Z3VH

After a few months, a PC will be dusty. There is usually at least 1 fan inside a PC case to move air in and out which means dust is being sucked through the case. Fan filters can help slow this down, but dust gets everywhere. At least every 6-12 months you should open your case and clean it out.

CPU coolers and graphics cards have fans and heat sinks, which are very prone to clogging with dust. If the heat sinks get clogged, the cooling performance is greatly reduced and you end up over heating. Ive personally killed a graphics card this way, and its pretty common for people to neglect this simple thing.

To clean the inside of your PC youll ideally use a compressed air duster. Simply blast away the dust. Youll need to be careful when blasting the CPU and GPU coolers, because you dont want the fans to spin up or they actually create a voltage. If a heat sink is especially clogged, you may want to use an old toothbrush. You should not use a vacuum directly on PC hardware because it can generate a large electro static charge, and if it discharges into your PC it can break hardware. You can keep a vacuum nearby to suck up the dust, just dont let any bare metal touch the PC. If it is very dusty, you might want to just take the PC outside where you wont need to worry about the dust kicking up. Also, if very dirty, you may have to remove parts from the PC, including taking fans off the heat sinks, to really get it clean. To avoid all this hassle, just clean it out more often.

This is just touching the surface, Ill be writing a few more maintenance posts in the future, the next one will have to do with keeping system performance up.

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Computer Worms

Computer Worms

A sub-class of a virus, a computer worm is a self replicating computer program that uses a network connection to spread from computer to computer extremely quickly, without the help of any executable host file or any person.

A computer worm therefore:

• Runs Independently
• Travels across network connections
• Has the capability to reproduce itself on your system

What worms can do?

With its ability to replicate itself rapidly, a computer worm overloads the system memory, causing slowdowns in data transmission due to massive bandwidth consumption.

If designed to do so worms can also carry a payload which can create a backdoor on your computer thereby allowing evil minded users to control your computers remotely.

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The Desktop Computer Comeback

Its senseless to do real computing on a laptop or iPad. For that, you need a big honkin desktop.

Although people spend all day with their iPhones, iPads or whatever else theyre using to casually search the web while watching TV or sitting at a cafe, most of them still have some sort of real computer on a desk somewhere. Some of these poor people (too many in fact) have been suckered into using a laptop as a desktop replacement. Theres really no such thing as a desktop replacement.

That said, the honkin desktop computer with the multi-core CPU isnt in vogue, plain and simple. The productivity benefits have been forgotten.

First of all, lets get real about computing in the modern world. Its not about looking things up on the Web; its about getting more work done in a shorter period of time than ever before. This is largely because of the processing power of desktop computers. And, yes, a powerful laptop can be a workhorse, but get real. If given a choice between using a laptop – no matter how powerful – with a 15-inch screen and using a multi-core tower machine with two or three or four 20-inch to 30-inch monitors, why would I choose the laptop?

Yes, the big rig will cost more, but with just one or two monitors, it wont cost that much more.

The drawback to the desktop rig, of course, is lack of portability. I dont know about you but I dont have this overwhelming desire to have a computer with me 24/7. Others do.

Ive noticed a few interesting phenomenon that bring us back to the olden days of the secretarial pool. Someone in your group will have an iPad or iPhone with an efficient Web browsing system. And the person will be adept at using these devices. Moreover, theyre more than willing to be your secretary to show off their skills on these devices.

"I think were lost, the restaurant isnt here."

"Let me pull out the iPad and figure out where we are."

"You do that while I go shopping."

Ive noticed myself barking commands to these people. "See what the capacity of that hall is. Ill bet its over 500." "Can you bring up a map of the area?" "See if there are any nearby ATM machines."

Never once does someone say, "Get an iPad and look it up yourself, you skinflint! Of course not, because they love using these machines and need a rationale for owning the things. Meanwhile, the machine that pays the bills is the desktop machine, and many of these same people use underpowered laptops for this function.

Im not sure why the buzz about desktops has waned to the point where nobody wants to talk about them. Theyre not totally uninteresting. Many use fiber connectors and have unusual architectures that are worth discussing. Maybe its too complicated for todays audience. After all, they think Facebook is high tech.

Well you can do what you want, but it just wont be as good or as fast unless its done on a big honkin machine. Get one today!

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PORTABLE COMPUTER

Defining the Portable Computer
Portables, like their desktop counterparts, have evolved a great deal since the days when the word portable could refer to a desktop-sized system with a handle on it. Today, much smaller portable systems can rival the performance of their desktop counterparts in nearly every way. Many portables are now being marketed as "desktop replacements," which are portable systems powerful enough to serve as a primary system. This chapter examines the phenomenon of portable computing, showing how it has evolved and why it is so popular.
Portables started out as suitcase-sized systems that differed from desktops mainly in that all the components, including a CRT-style monitor, were installed into a single case. In the early 1980s, a small Houston-based startup company named Compaq was among the first to market portable PCs such as these. Although their size, weight, and appearance are almost laughable when compared to todays laptop or notebook systems, they were cutting-edge technology for the time. In fact, unlike modern laptops, the components used by these bulky first generation portables were virtually identical to those used in the most powerful desktops of the day.
Most current portable systems are now approximately the size of the paper-based notebook they are often named for and are built using the clamshell design that has become an industry standard. Inside these systems, nearly every component has been developed specifically for use in mobile systems.
Portable PCs, however, are not the same as Personal Digital Assistants (PDAs), such as the Palm series, Handspring, and PocketPC. Portable computers differ from PDAs in that they use the same operating systems and application software as desktop computers and use memory, CPU, and drive technologies that are similar to desktop PCs as well. PDAs, on the other hand, use different operating systems, applications, and hardware compared to either desktop or portable PCs and thus fall outside the scope of this book. Instead, this book focuses primarily on laptops or notebook-style portable PCs. That said, in terms of technology, much of this book will also be applicable to a relatively new category of portables: Tablet PCs. Actually Tablet PCs have been around since the early 90s, but a lack of standardized software, combined with relatively low power and functionality, limited them to special applications rather than mainstream use. In many respects, modern Tablet PCs are identical to laptop/notebook computers except that they are equipped with a touch-sensitive display, lack the integrated removable storage (such as a CD/DVD-ROM drive), and include a special tablet-oriented version of Windows. While most include a keyboard and basically look like a standard notebook computer, a few Tablet PCs do not come with a keyboard at all. Those that dont include a keyboard generally offer one as an accessory or can use any standard external keyboard if desired.
Many people use portable systems as an adjunct or accessory to a primary desktop system in their principal working location. In those cases, the portable system may not need to have all the power of a desktop, since it will only be used when away from the main office. In my situation, the roles are reversed. All my professional life I have been teaching PC hardware and software, usually on the road. As such I have always needed a powerful computer I can take with me, and because the amount of time spent traveling is equal to or more than the amount of time spent at a home office, I have had to rely on portable PCs of one type or another as my primary system.
All my books on upgrading and repairing PCs, starting with my first self-published seminar workbooks in 1985, have been written on a portable system of one type or another. With the processing power of modern laptop/notebook systems evolving to the point where they are nearly equal to all but the most powerful desktop systems, I look forward to carrying even smaller, lighter, and more powerful laptops in the future.
Portable computers have settled into a number of distinct roles that now determine the size and capabilities of the systems available. Traveling users have specific requirements of portable computers, and the added weight and expense incurred by additional features make it less likely for a user to carry a system more powerful than is necessary. Others may not do much traveling, but simply like the flexibility and small footprint that a laptop provides.

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