Definition of: modem

(MOdulator-DEModulator) Until the late 1990s, the term referred to a device that allows a computer or terminal to transmit data over a standard dial-up telephone line. Since the advent of cable and DSL connections, the term commonly refers to high-speed broadband modems.

This definition pertains only to dial-up modems, also known as "analog modems," which convert digital pulses from the computer to audio tones that analog telephone lines can carry, and vice versa. V.92 is the last dial-up standard, providing a data rate of 56 Kbps.

New computers geared for home users may or may not have a built-in analog modem, while those targeted for the office typically do not. However, a modem can be added internally via a PCI card, or externally via a USB port.

Like a Telephone
A modem dials the line and answers the call. It performs the digital-to-analog and analog-to-digital conversion while controlling transmission speed. Whatever the top speed, some number of lower speeds are also supported to accommodate old modems or negotiate downward on noisy lines. Over the years, speeds evolved from 300 bps to 56,000 bps (56 Kbps).

Error Correction and Compression
Modems have built-in error correction (V.42) and data compression (V.42bis, MNP 5). On files that are already compressed, the modem's data compression has no value. Modems also have automatic feature negotiation, which adjusts to the speed and hardware protocols of the modem on the other end.

The Hayes Standard
Most modems use the Hayes AT command set, which are machine instructions for modem control. The term modem has been used as a verb; for example, "I'll modem you later.

The Sportster Modem

This was a hot-selling product in the 1990s as people went online in record numbers. External units have the advantage of status lights for troubleshooting connections. Internal modems since became the norm. (Image courtesy of 3Com Corporation.)

A Rack of Hayes Modems

The pioneer in personal computer modems, Hayes set the standard for control commands. This rack-mounted model allowed any of its 16 modem cards to be hot swapped. Devices like this were installed by the thousands at large ISPs. (Image courtesy of Hayes Microcomputer Products, Inc.)

Definition of: cable modem

A device used to connect a single computer or a network to a cable company's service for Internet access. The same physical cable coming into the house or office also provides TV and voice (VoIP) service.

Compared to analog dial-up, cable Internet dramatically increases the bandwidth between the user's computer and the Internet. In order to prevent users with lower-cost cable access from hosting high-traffic Web servers, the upload speed is approximately five times slower than the download speed. Cable operators also routinely change IP addresses assigned to users to prevent Web hosting.

Connect Via Ethernet or USB
Cable modems typically connect to the computer or network router via an Ethernet port; however, some cable modems have a USB port for hookup to the computer but not the network.

Cable Internet is a shared service, and the individual user's speed will vary depending on how many customers are sending or receiving data on that cable segment at the same time. For example, when kids come home from school in the afternoon, many neighborhood users experience slower speeds.

A Cable Modem System

Internet packets are combined with standard TV programming in a cable modem system. The cable modem termination system (CMTS) is responsible for packet to RF conversion, routing, bridging, filtering and traffic shaping (see CMTS).

IncrediMail Free Email Program

The Bottom Line

IncrediMail is a fun and easy to use email client that adds spice to the messages you send while protecting you from spam, phishing and fraud attempts in a convenient manner.
Unfortunately, IncrediMail lacks some productivity features if you have to deal with large amounts of mail.

• IncrediMail is a friendly program, easy and a lot of fun to use
• Plenty of stationery and multimedia content is available for IncrediMail
• IncrediMail offers fast search and can organize email folders in a useful fashion

Cons

• IncrediMail supports IMAP accounts only in a very limited and rudimentary way
• Secure, encrypted email messaging is not available in IncrediMail
• IncrediMail does not offer templates, text snippets and learning filters for efficient email use

Description

• IncrediMail lets you access multiple POP, IMAP (download-only) email accounts.
• Large collections of stationery, animations, emoticons and sounds can be used in IncrediMail emails.
• IncrediMail sports animated new mail notifiers, 3D effects and animations throughout.
• Basic message rules, a fast search engine, flags and folder filters help you organize email in IncrediMail.
• You can set up IncrediMail to accept only mail from approved senders into your inbox.
• IncrediMail Protection Center, a subscription service, filters spam and alerts you about links to harmful sites in emails.
• IncrediMail can block remote images in emails (problematic privacy-wise) and lets you bounce mail.
• It is easy to transfer IncrediMail data and settings to a new computer. Paid option IncrediBackup offers simple backups.
• Anonymous usage data collected by IncrediMail identifies the most popular letters and other content.
• IncrediMail supports Windows XP/Vista/7.

Guide Review - IncrediMail 2 6.26 - Free Email Program

Email is most fun when it works — and includes flashy trinkets, too. Of the latter, IncrediMail has plenty: you can send and receive messages using rich formatting, of course, or apply rich stationery (called IncrediMail letters), add handwritten signatures, send e-cards, insert sounds and what not; you can also change IncrediMail's (somewhat homespun) interface with themes, have animated characters announce new mail and have typewriter sounds accompany your, well, typing.

IncrediMail also works. It downloads mail faithfully from multiple (POP and IMAP, including, e.g., Windows Live Hotmail, Gmail and AOL Mail, of course) accounts into ever growing folders. Thanks to handy search functions, you can focus on certain messages — say, mail from a particular sender, attachments or unread emails — easily in a folder or, of course, search all your archive for keywords and characteristics swiftly.
What is true for emails also applies to people: they are easy to add and to find, can have distinguishing icons or pictures assigned. IncrediMail will also suggest likely people to remember based on your correspondence patterns, and managing groups is a breeze.

Unfortunately, IncrediMail is not so helpful and courteous with composing messages. You can set up signatures, of course, and have IncrediMail send out-of-office replies; IncrediMail does not, however, include message templates or text snippets for faster answers. Free-form message labels or self-learning folders to organize mail in a very personal or totally automatic manner are missing as well.

You can subscribe to a capable spam filter, though, and IncrediMail comes with messages filters that muster the essential tasks. Speaking of subscriptions, it is really unfortunate that IncrediMail's IMAP support is lacking: you can only download new mail, not subscribe to folders and access their online contents.

Disabling AutoRun

Below are several steps to turn off autorun in your computer:

• Click Start - Run.
• Type "regedit".
• Go to HKEY_CURRENT _USER\Software\Microsoft\ Windows\CurrentVersion\Policies\Explorer.
• On the right window of registry editor, right-clickNoDriveTypeAutoRun.
• Click Modify.
• Change value data into "ff" to disable autorun function on the drive.
• Click OK.
• Then go to HKEY_USERS\.DEFAULT\Software\Microsoft\ Windows\CurrentVersion\Policies\Explorer.
• Do the same things as previous steps.
• Exit fromRegistry Editor.
• Restart the computer.

Low Disk Space Warning

When the space of your hard disk is low, Windows will usually give "low disk space" warning on the system tray. This warning sometimes disturbs us. To stop this warning from appearing, do the following steps:

1. Click Start - Run.
2. Type "regedit".
3. Go to HKEY_CURRENT USER\Software\Microsoft\Windows\CurrentVersion\Policies\Explorer.
4. On the right window of registry editor, right-click the empty space.
5. Choose New - DWORD Value.
6. Type the value name "NoLowDiskSpace" and press Enter.
7. Right-click the new key you've made and choose Modify.
8. On the Value Data type the number "1".
9. Press OK.
10. Restart your computer.

Get a Free Premium Domain Name .Net .Com .Org

Below is a Website offers you to register a free premium Domain name for free all you need to just sign up and reffer others friends and get a free doamin name.
http://www.FreePremiumDomain.com/?r=239184

Google Launches a New Service for Pakistan ‘Google Places’

Are you using Google Places Yet?

As you become familiar with Google Places and update your listings on a regular basis, you’ll discover hundreds of advantages for advertising your business through this free service. Listed below are 10 advantages worth mentioning.

1. Online advertising like Google Places is the way of the future, and it will soon replace paper phone directory listings that cost thousands of dollars per year.
2. Google Places is free.
3. When your Google Places listing is optimized properly, your business listing appears on the first page of Google.
4. You can offer discounts and coupons for one day, one week, or one month.
5. Your website, physical mailing address, and your phone number are displayed in your listing, which allows customers to find you more quickly and to get the information they need.
6. Mobile phone users can find your business listing immediately, and they don’t need a computer to do it.
7. You will receive more traffic and new customers.
8. You don’t need a physical retail or warehouse location to get accepted into Google Places.
9. By using citations and reviews, your Google Places will move up in ranking. With high ranking, within eight weeks, rather than eight months or eight years, your free advertising with Google Places will bring you more targeted customers faster than traditional organic methods.
10. Finally, and the most important to your financial goals, is that because it is so easy for customers to find your business listing, you will make more money than you did before your business was listed in Google Places.
Whether you are going to set up and claim your Google Places page on your own, or have someone do this service for you, the sooner you have your Google Places page working for you, the quicker your customers will find you.

PTCL has Commercially Launched the EVO Nitro 3G 9.3 MB

PTCL (Pakistan Telecommunication Company Limited)  has commercially launched the EVO Nitro 3G.
So far, it is the fastest and widely available data service in Pakistan. EVO 3G Nitro is all set to meet the next-generation’s need for ultimate speed & superior performance with speed up to 9.3mbps.
PTCL claims that with this launch, Pakistan has become the first country in the world to provide this EV-DO Rev B 3G technology.

EVO 3G Nitro has revolutionized the three simple steps to high speed On-the-Go connectivity, Just Plug in—Click—Connect with its unprecedented speed of up to 9.3 Mbps on the downlink and up to 5.4MBPS on the uplink based on EV-DO Rev B 3G CDMA  technology.

Tariff:

• Nitro USB Device Charges: Rs. 3,999
• Nitro Unlimited Service Charges: Rs. 2,999 per month

Billing Options:

• Nitro Landline Billing: Billed in PTCL Landline
• Nitro Advance Billing: Advance payment at PTCL OSS or PTCL designated banks

Coverage Area:

Nitro “Rev.B” Coverage is offered in following cities:

• Islamabad,
• Rawalpindi,
• Lahore
• & Karachi.

Data Rate:

Average data rates vary between 1.25 Mbps- 3.75 Mbps

How Current EVO customers can Upgrade to Nitro?

If you wish to upgrade you are required to return your existing USB device and pay additional charges of Rs.1000.
In exchange you will get a brand new Evo 3G Nitro USB device and need to sign up for Nitro package. Visit your nearest PTCL One Stop Shop for more details.
Existing USB device must be in perfect physical and working condition and returned with box.
SEVP Commercial Naveed Saeed at the occasion of this commercial launch said:

EVO 3G Nitro has been launched with the aim of giving our customers a far more enhanced user experience of instant connectivity. He further added that it’s a step ahead in the development and prestige of the technologically strong and revolutionary telecom company. This deployment has reinforced the company’s technological lead in the sector and Working in a market where technology changes every minute, we at PTCL always strive to introduce products and services that add more value to our customers’ lives, and PTCL’s ‘EVO 3G Nitro’ is one such product that will completely revolutionized the way our customers communicate.”

Syed Asim Ali, EVP Commercial Planning said:

the launch of Evo Nitro 3G is a milestone and a glorious mark in the conquest of PTCL, EVO 3G Nitro saves the precious time of our customers, PTCL customers can now for the very first time spend less time waiting and more time working and accessing media rich applications from downloading songs to live video streaming, at home on your desktop or on the move on your laptop. He further added that In future PTCL plans to introduce a variety of innovative services that can enhance our customer’s life, which is our first and foremost priority.

Over 2 Million Students in Punjab to Get Computers Education

Government of Punjab will save Rs. 1.8 billion by using NComputing in over 4,000 schools
More than 2 million students in Punjab, Pakistan will soon receive computer education for the first time with the help of NComputing’s ultra low-cost virtual desktops. The Chief Minister of the Punjab has driven the program, which is setting up computer laboratories in more than 4,000 government-owned secondary and higher secondary schools.

NComputing virtual desktops have revolutionized learning in developed and developing countries by making computer access more affordable than ever before. The solution takes advantage of the fact that today’s computers are so powerful that the vast majority of applications use only a small fraction of the computer’s capacity. NComputing enables a single computer to be virtualized so that many users can tap the unused capacity and share it as if each person had their own computer.

In Punjab, each school will be furnished with a 15-seat computer lab will be run on 3 desktop PCs and 12 NComputing virtual desktops that will connect to the PCs. In addition to reducing purchase costs, electricity usage for these labs will be 90 percent lower than a traditional all-PC computer lab. Finally, when the useful life of the PCs is complete, only a few PCs will need to be upgraded – saving even more funds.
“It is a sustainable and environment-friendly project with very low recurring costs. In the overall context of the project, we are saving over Rs. 1.8 billions, which is almost 36% of the total project cost. As far as the electricity savings is concerned, the Government of Punjab would save another over Rs. 10 million per month as the NComputing devices use only 1 watt of electricity as compared to 110 watts or more for a typical PC,” says the IT Labs project’s Additional Programme Director Joudat Ayaz. “We have reduced the number of PCs being purchased and the cost of uninterruptible power supplies (UPS) has also been drastically reduced”.

“With the NComputing technology, a new era in computer literacy has started in Punjab which will enable the provincial planners to impart meaningful computer training at low cost,” said Mr. Saiyid Hasan Rashaad, VP of NConnexion, NComputing’s distributor and authorized service center for Pakistan & Afghanistan.

“NComputing is proud to have been chosen by the Government of Punjab to enhance computer literacy and to equip the future workforce of the country with the computing skills they need to compete on a global economy,” said Mr. Manish Sharma, Vice President of Asia-Pacific for NComputing. “NComputing has become a valuable contributor to the lives of millions of people across tens of thousands of institutions and organizations in more than 140 countries. We continuously endeavor to enable schools, businesses, and governments to expand and improve their computing capabilities at extremely affordable and sustainable costs.

Windows 7 Sales Exceed than Windows vista

The Windows 7 sales have exceeded that of Sale Vista by 234% and it is so interesting to watch the sales rate increasing day by day. Even with the post economic flux there is significant growth within a some weeks of the release of Windows 7.

This is quite an outstanding result considering that it has out shone the release of Harry Potter second last film. The NPD Group’s weekly tracking service have come up with new sales pitching and combination of facts that have been impaired with some of the more significant tracking services with the Windows 7 software feature.

How to Use a TV as a Monitor

 

There are lot of  ways to connecting PC to TV. Some users use usual TV tuner cards for displaying their PC’s output on TV, while others use S-Video mode or otherwise through dedicated graphics card installed in PCs.
However, “VGA to RCA Cable” happens to be the simplest way of connecting PC with TV.

In VGA to RCA Cable, as its name suggests, one side of the cable has VGA (usual Monitor) connector while other side has RCA cable connector (Audio/Video, Red, Yellow and White Pins).
This makes really easy to connect a PC with TV without installing any particular device like TV tuner or software to make it working. Simply connect and Hurray!

VGA to RCA cable provide several benefits like watching movies, displaying family pictures and videos on your big screen TVs just by connecting cables.

What to consider before buying?

• There is slight difference between VGA to RCA Plug Cable and VGA to RCA Component Plug Cable. Component cable carries component video into two or more components with YPbPr scheme. Ask seller about the functionality of RCA Plug, for instance, they usually support RG Analog and digital component video. If it is digital component video plug then it can handle 480i, 576i and other high definition TV support.
• Usually RCA connector is easily identified with its RED, YELLOW and WHITE plugs, carrying composite video on YELLOW and stereo audio on RED and WHITE.
• Component Cable connectors are identified as having RED, GREEN and BLUE plugs.
• Some VGA to RCA cables comes with built-in S-Video cable as well. If that’s the case, go for it for added features.

Usage benefits:

• It can be used with TV for watching movies.
• It can be used with projectors.

Availability in Pakistan:
VGA to RCA cable is easily available in Pakistan. Its price ranges from PKR 400 to PKR 700. Do check price variations by visiting more than one shop for buying products.

Sale of Used Computers

The sale of used computers is on rise in Pakistan because of high prices of new brand computers. The used computer stockholders selling monitors, mouse & other used accessaries at various shopping malls & corners of the provincial metropolis to attract the visitors. Shoppers are roaming the markets, checking out the varieties in different designs & quality.

Due to pressing demands of kids, most of parents reluctantly visit markets for used computers & other toys. The shopkeepers have displayed a variety of equipment. A used computer stall owner, Anzar Malik told APP, that most of the people preferred buying used accessaries & computers from his shop as the prices are not affordable for new computers.

They said that most of students depend on used computers, because the new computer required more money so students get from the used markets. Another resident Majid said that Rawalpindi is the hub of used electronics items & people always preferred to get any workable item from the stock. They said that sixth road is two of the famous place for computers parts & most of the people specially visit to search any workable set.

They said that hundreds of shops of used computers are obtainable in different markets of the city. An IT specialist Shafqatullah said that several time very valuable items are coming in this used stocks & people depend on it for their work.

In Pakistan Buy Pentium 4 Computer in KG Rate

 

Used Computers are availabe in very low prices in pakistan the Top brand eg. HP,COMPAQ,DELL,IBM,APPLE the new system price of these brands are very high.We cant afford these brands price in pakistan but the used computers are a big hope in information technalogy progress in pakistan.

Windows XP Repair

Windows XP is probably the most familiar Windows Operating System to most users. It is a stable system that generally functions properly. As with any operating system, there can still be problems that occur and damage the operating system. When this happens, run an error scan to pinpoint the specific errors and potentially correct them if the software is capable of doing so. Be familiar with the causes of damage to Windows.

Click Here to Download & Repair Windows XP!

Malware can cause damage to the Windows Registry and OS files, as well as general data corruption and registry damage. This is part of the reason it is important to run a registry scan and cleanup utility before installing any new software. Problems with Windows XP can range from minor to severe. The most severe case would be damage to the extent that Windows XP will no longer boot or operate. This is when Windows XP Repair is essential to restore operating system function. There are several ways to approach Windows XP Repair. One of the advantages of Windows XP, is that it comes with a built in repair feature capable of restoring the operating system to the original working condition. If Windows XP repair is necessary, and Windows XP will not boot, the Windows XP repair feature can still be used. To achieve Windows XP repair in the event of operating system damage, you will need your original Windows XP installation CD.

The first step to Windows XP repair is to insert the Windows XP installation CD into the Optical Drive. Next, reboot the computer to initiate Windows XP repair. You will be prompted to select whether you wish to boot from the CD or the standard file. To properly initiate Windows XP repair from the menu, do not boot from the standard file. Instead, boot from the Windows XP installation CD. If you are not prompted to choose a reboot option, restart the computer one more time and press “F12″ on the BIOS page. This will open the boot options menu. To begin Windows XP repair from the installation CD, select the drive that contains the CD and press “Enter.”
Soon, the “Welcome to Setup” page will be presented. Now you can begin to all of the steps for windows XP repair. Three options will be presented to you, however, ignore these three options and simply press “Enter” and go directly to Windows XP setup. To initiate proper Windows XP repair from this window, it is important that you do not select the option to launch the Recovery Console.
The next step in this Windows XP repair process is to press the “F8″ key once the licensing agreement page opens. This simply indicates that you accept the licensing agreement. In order to proceed with Windows XP repair, it is required that you accept the licensing agreement terms even though you have accepted them before with your original Windows XP installation. A list containing your current Windows XP installation will be presented. Select your current Windows XP installation, and then press the “R” key and this will initiate Windows XP repair. Follow all on-screen prompts and this will lead you through the Windows XP repair process. All damaged files will be overwritten and none of your saved data is lost during the Windows XP repair process.
Once Windows XP repair is complete, the computer will reboot. At this time, remove the installation CD from the drive in order to avoid any complications upon startup. After following these easy steps, Windows XP repair has been achieved and your operating system will now boot up without difficulties.

What is Worm, Trojan and Horse?

The most common blunder people make when the topic of a computer virus arises is to refer to a worm or Trojan horse as a virus. While the words Trojan, worm and virus are often used interchangeably, they are not exactly the same. Viruses, worms and Trojan Horses are all malicious programs that can cause damage to your computer, but there are differences among the three, and knowing those differences can help you to better protect your computer from their often damaging effects.

Virus:
A computer virus attaches itself to a program or file enabling it to spread from one computer to another, leaving infections as it travels. Like a human virus, a computer virus can range in severity: some may cause only mildly annoying effects while others can damage your hardware, software or files. Almost all viruses are attached to an executable file, which means the virus may exist on your computer but it actually cannot infect your computer unless you run or open the malicious program. It is important to note that a virus cannot be spread without a human action, (such as running an infected program) to keep it going. People continue the spread of a computer virus, mostly unknowingly, by sharing infecting files or sending e-mails with viruses as attachments in the e-mail.

Worm:

A worm is similar to a virus by design and is considered to be a sub-class of a virus. Worms spread from computer to computer, but unlike a virus, it has the capability to travel without any human action. A worm takes advantage of file or information transport features on your system, which is what allows it to travel unaided. The biggest danger with a worm is its capability to replicate itself on your system, so rather than your computer sending out a single worm, it could send out hundreds or thousands of copies of itself, creating a huge devastating effect. One example would be for a worm to send a copy of itself to everyone listed in your e-mail address book. Then, the worm replicates and sends itself out to everyone listed in each of the receiver's address book, and the manifest continues on down the line. Due to the copying nature of a worm and its capability to travel across networks the end result in most cases is that the worm consumes too much system memory (or network bandwidth), causing Web servers, network servers and individual computers to stop responding. In recent worm attacks such as the much-talked-about Blaster Worm, the worm has been designed to tunnel into your system and allow malicious users to control your computer remotely.

Trojan Horse:

A Trojan Horse is full of as much trickery as the mythological Trojan Horse it was named after. The Trojan Horse, at first glance will appear to be useful software but will actually do damage once installed or run on your computer. Those on the receiving end of a Trojan Horse are usually tricked into opening them because they appear to be receiving legitimate software or files from a legitimate source. When a Trojan is activated on your computer, the results can vary. Some Trojans are designed to be more annoying than malicious (like changing your desktop, adding silly active desktop icons) or they can cause serious damage by deleting files and destroying information on your system. Trojans are also known to create a backdoor on your computer that gives malicious users access to your system, possibly allowing confidential or personal information to be compromised. Unlike viruses and worms, Trojans do not reproduce by infecting other files nor do they self-replicate.

What is a Computer Virus ?

In my Previous article I explained about malware .In todays post i will be explaining about Computer Virus which is a type of malware

A computer virus is a program which reproduces itself. It may attach to other programs, it may create copies of itself (as in companion viruses). It may damage or corrupt data, change data, or degrade the performance of your system by utilizing resources such as memory or disk space.

There are thousands of viruses, and new ones are discovered every day. It is difficult to come up with a generic explanation of how viruses work, since they all have variations in the way they infect or the way they spread. So instead, we'll take some broad categories that are commonly used to describe various types of virus.

File Viruses (Parasitic Viruses):-

File viruses are pieces of code that attach themselves to executable files, driver files or compressed files, and are activated when the host program is run. After activation, the virus may spread itself by attaching itself to other programs in the system, and also carry out the malevolent activity it was programmed for. Most file viruses spread by loading themselves in system memory and looking for any other programs located on the drive. If it finds one, it modifies the program's code so that it contains and activates the virus the next time it's run. It keeps doing this over and over until it spreads across the system, and possibly to other systems that the infected program may be shared with. Besides spreading themselves, these viruses also carry some type of destructive constituent that can be activated immediately or by a particular 'trigger'. The trigger could be a specific date, or the number of times the virus has been replicated, or anything equally trivial. Some examples of file viruses are Randex, Meve and MrKlunky.

Boot Sector Viruses:-

A boot sector virus affects the boot sector of a hard disk, which is a very crucial part. The boot sector is where all information about the drive is stored, along with a program that makes it possible for the operating system to boot up. By inserting its code into the boot sector, a virus guarantees that it loads into memory during every boot sequence.


Multipartite Viruses:-

Multipartite viruses are a combination of boot sector viruses and file viruses. These viruses come in through infected media and reside in memory. They then move on to the boot sector of the hard drive. From there, the virus infects executable files on the hard drive and spreads across the system. There aren't too many multipartite viruses in existence today, but in their heyday, they accounted for some major problems due to their capacity to combine different infection techniques. A significantly famous multipartite virus is Ywinz.

Macro Viruses:-

Macro viruses infect files that are created using certain applications or programs that contain macros. These include Microsoft Office documents such as Word documents, Excel spreadsheets, PowerPoint presentations, Access databases, and other similar application files such as Corel Draw, AmiPro, etc. Since macro viruses are written in the language of the application, and not in that of the operating system, they are known to be platform-independent they can spread between Windows, Mac, and any other system, so long as they're running the required application. With the ever-increasing capabilities of macro languages in applications, and the possibility of infections spreading over networks, these viruses are major threats.

The first macro virus was written for Microsoft Word and was discovered back in August 1995. Today, there are thousands of macro viruses in existence-some examples are Relax, Melissa.A and Bablas.

Network Viruses:-

This kind of virus is proficient in quickly spreading across a Local Area Network (LAN) or even over the Internet. Usually, it propagates through shared resources, such as shared drives and folders. Once it infects a new system, it searches for potential targets by searching the network for other vulnerable systems. Once a new vulnerable system is found, the network virus infects the other system, and thus spreads over the network. Some of the most notorious network viruses are Nimda and SQLSlammer.

E-mail Viruses:-

An e-mail virus could be a form of a macro virus that spreads itself to all the contacts located in the host's email address book. If any of the e-mail recipients open the attachment of the infected mail, it spreads to the new host's address book contacts, and then proceeds to send itself to all those contacts as well. These days, e-mail viruses can infect hosts even if the infected e-mail is previewed in a mail client. One of the most common and destructive e-mail viruses is the ILOVEYOU virus.

There are many ways in which a virus can infect or stay dormant on your PC. However, whether active or dormant, it's dangerous to let one loose on your system, and should be dealt with immediately.

Computer Viruses (what is good)

"The Internet is a totally connected infrastructure," said Steve Trilling, senior director of research at Symantec. "That means we're only as strong as the weakest link." If every computer user simply protected his or her own laptop or PC, Trilling said, virus and worm writers would have to pursue another form of entertainment.

Ahhh-choo! Ahh, lucky you. Every time you are exposed to a virus, your immune system builds resistance to that particular bug. So, why can't we build computers that do the same thing?

"If our bodies functioned like computers, we'd be extinct," said Steve Hofmeyr, founder and chief scientist of Sana Security. "The body is a dynamic place that profits from changes," he told TechNewsWorld. "Our immune systems adapt with us from birth to puberty and through the aging process."
Perhaps the promise of biological computing is that our machines will grow up, rather than grow obsolete. But while it's easy to draw analogies between how the human immune system works and how virus protection software programs should work, mimicking nature is no simple task.

Designing Survivability

According to David Evans, professor of computer science at the University of Virginia, we may not be able to develop computer programs that mimic biology exactly, but we can learn techniques from biology that enable us to build more scalable and robust systems. Several of Evans' projects are supported by National Science Foundation (NSF) grants.

"Our goal is to produce complex, predictable behavior from a large number of unreliable components," he said. Someday, Evans added, our computers could manage to remain up and running even as new viruses spread, "...the same way an organism survives even when its cells fail and its environment changes."
He noted that we can learn from studying other natural defense mechanisms, such as decentralization and diversity. "Immune systems are part of the solution, but not all of it -- neither in computer systems nor in nature," Evans explained. "The success of the immune system relies on organisms continuing to function even after a few cells are infected, so the body has time to produce enough antibodies to react," he told TechNewsWorld.
"I think the future of computing will depend on both directions of research -- changing the way systems are built to make them intrinsically less vulnerable, and developing immune systems for mitigating attacks," Evans said.

Bad Bugs Teach Good Habits

Unfortunately, the environment in which our computers live -- that is, the world of the Internet -- is increasingly hostile. Every new virus and worm seems to spread more quickly than the last. And we have ourselves to blame.
"The Internet is a totally connected infrastructure," said Steve Trilling, senior director of research at Symantec (Nasdaq: SYMC). "That means we're only as strong as the weakest link." If every computer user simply protected his or her own laptop or PC, Trilling said, virus and worm writers would have to pursue another form of entertainment.
On the bright side, a computer user who suffers the effects of a virus typically responds like the heart-attack survivor who, overnight, adopts healthy habits. Each time a new virus is reported, we download patches and upgrade security systems in droves. After the SoBig attack last fall, hundreds of thousands of computer users updated software, installed virus protection and reconfigured firewalls.
Microsoft's (Nasdaq: MSFT) TechNet saw a more than 1,000 percent increase in unique visitors the week SoBig hit; Symantec's online unique visitor count increased more than 300 percent.
The good news about malware, then, is that each new worm, virus or blended threat encourages more users to develop "healthy" habits. Theoretically, at least, that should make for a stronger Internet environment.
Trilling noted that there is widespread interest in developing antivirus and data recovery systems that mimic our bodies' natural defenses. But while Symantec's current products incorporate some artificial intelligence, such as learning to recognize real threats versus legitimate user behavior, Trilling said systems that are truly self-recovering are still in early research phases.

Building Immunity

Like Evans, Sana Security's Hofmeyr has spent years contemplating bugs of both the electronic and biological sort. After completing his undergraduate degree in computer science and writing a masters thesis on genetic algorithms, Hofmeyr studied with leading immunology researchers at the University of New Mexico and others at MIT's Artificial Intelligence Lab. Now, he told TechNewsWorld, his goal at Sana Security is to realize a mode of computing that is "much more biological in nature."
To that end, the company developed Primary Response, a server-based software system that, like our bodies' immune systems, learns from both user actions and external stimulus. The U.S. Air Force was among the first installations, he said.
Hofmeyr admits designing computers to be more like humans isn't easy. For one thing, he pointed out, "We don't know how half of our immune system works." But the quest is worthwhile, he said -- and not merely for the sake of creating virus-resistant, self-healing machines. Hofmeyr believes that when we design computers that more closely mimic nature, they will also be inherently more user-friendly.
"People don't work with computers so much as they struggle with them," he told TechNewsWorld, "because people haven't evolved to work with computers." When we design computers that are more biological in nature, he noted, we will realize other benefits. Specifically, Hofmeyr said he hopes to see a more natural interface between man and machine.

Meanwhile, Take Your Vitamins

While we await evolutionary changes in computer-human relations, new threats in our current computing environment appear almost daily.
As Evans put it, "The key to having secure systems is to have designs where the impact of a single vulnerability is limited, and where the system can recover from attacks faster than the attackers can launch them."
So what's a computer user to do?
Until that day arrives when our computers can literally take care of themselves, a few preventive actions can go a long way toward keeping your system healthy. In other words, download your security patches, update your software, and wash your hands -- just in case.

Old Computer Fun

Early personal computers were nothing like present day computers, they had personality!

Each was different and more exciting than the previous, with new features and capabilities.

This website is dedicated to the preservation and display of these vintage computer systems.

To the left you can examine these computers from the dawn of time and re-live the past, possibly YOUR past! "Click" on any system to learn more and view recent pictures.


Browse the old computer ads, and have a chuckle at early attempts to convince the consumer which computer was "right for you!".

For fun, all 100 old computers at the same time to appreciate how diverse and interesting they are.

25 things you never knew about old computers.

Feel free to contact us for more information, to sell us your old system, or to learn more about this website.

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