VIRUS
Perhaps the most well known computer security threat, a computer virus is a program written to alter the way a computer operates, without the permission or knowledge of the user. A virus replicates and executes itself, usually doing damage to your computer in the process.
SPAM
What is spam?Spam is flooding the Internet with many copies of the same message, in an attempt to force the message on people who would not otherwise choose to receive it. Most spam is commercial advertising, often for dubious products, get-rich-quick schemes, or quasi-legal services. Spam costs the sender very little to send -- most of the costs are paid for by the recipient or the carriers rather than by the sender.
There are two main types of spam, and they have different effects on Internet users. Cancellable Usenet spam is a single message sent to 20 or more Usenet newsgroups. (Through long experience, Usenet users have found that any message posted to so many newsgroups is often not relevant to most or all of them.) Usenet spam is aimed at "lurkers", people who read newsgroups but rarely or never post and give their address away. Usenet spam robs users of the utility of the newsgroups by overwhelming them with a barrage of advertising or other irrelevant posts. Furthermore, Usenet spam subverts the ability of system administrators and owners to manage the topics they accept on their systems.
Email spam targets individual users with direct mail messages. Email spam lists are often created by scanning Usenet postings, stealing Internet mailing lists, or searching the Web for addresses. Email spams typically cost users money out-of-pocket to receive. Many people - anyone with measured phone service - read or receive their mail while the meter is running, so to speak. Spam costs them additional money. On top of that, it costs money for ISPs and online services to transmit spam, and these costs are transmitted directly to subscribers.
One particularly nasty variant of email spam is sending spam to mailing lists (public or private email discussion forums.) Because many mailing lists limit activity to their subscribers, spammers will use automated tools to subscribe to as many mailing lists as possible, so that they can grab the lists of addresses, or use the mailing list as a direct target for their attacks.
There are two main types of spam, and they have different effects on Internet users. Cancellable Usenet spam is a single message sent to 20 or more Usenet newsgroups. (Through long experience, Usenet users have found that any message posted to so many newsgroups is often not relevant to most or all of them.) Usenet spam is aimed at "lurkers", people who read newsgroups but rarely or never post and give their address away. Usenet spam robs users of the utility of the newsgroups by overwhelming them with a barrage of advertising or other irrelevant posts. Furthermore, Usenet spam subverts the ability of system administrators and owners to manage the topics they accept on their systems.
Email spam targets individual users with direct mail messages. Email spam lists are often created by scanning Usenet postings, stealing Internet mailing lists, or searching the Web for addresses. Email spams typically cost users money out-of-pocket to receive. Many people - anyone with measured phone service - read or receive their mail while the meter is running, so to speak. Spam costs them additional money. On top of that, it costs money for ISPs and online services to transmit spam, and these costs are transmitted directly to subscribers.
One particularly nasty variant of email spam is sending spam to mailing lists (public or private email discussion forums.) Because many mailing lists limit activity to their subscribers, spammers will use automated tools to subscribe to as many mailing lists as possible, so that they can grab the lists of addresses, or use the mailing list as a direct target for their attacks.
TROJAN HORSE
What is a Trojan Virus?A Trojan horse, often shortened to Trojan, is a type of malware designed to provide unauthorized, remote access to a user’s computer. Trojan horses do not have the ability to replicate themselves like viruses; however, they can lead to viruses being installed on a machine since they allow the computer to be controlled by the Trojan creator. The term gets its name from the Greek story of the Trojan War, when the Greeks offered the Trojans a peace offering in the form of a large wooden horse. However, once the Trojans wheeled the horse behind their closed gates and night fell, the soldiers hidden inside the horse climbed out and opened the city gates, allowing the Greek army to infiltrate Troy and capture the city. Trojan horse software operates the same way, where Troy is your computer and the horse is the benign-seeming application. Trojan horses can assist an attacker into turning a user’s computer into a zombie computer, stealing various data such as credit card information, installing more malware, keylogging and various other malicious activities. Also, it is possible for other crackers to control the compromised computer simply by searching for computers on a network using a port scanner and finding ones that have already been infected with a Trojan horse. Trojan horses continue to increase in popularity and currently account for the majority of known malware found on the web.
A trojan horse is a program or utility that appears to be something useful or safe, but in reality is performing background tasks such as giving access to your computer or sending personal information to other computers. Trojan horses are one of the most common methods a criminal uses to infect your computer and collect personal information from your computer. Below are some basic examples of how your computer could become infected with a Trojan horse.
1. A site offers a free download to a program or game that normally costs money. Downloading the pirated version of a program or game allows you to illegally use or play it, however, during the install it also installed a Trojan horse onto the computer.
2. A popular screen saver website has become infected or uploaded infected screen savers. Downloading the screen saver to your computer also installs a Trojan horse onto the computer.
3. You receive an e-mail that appears to be from a friend asking you to view this fantastic new program or look at a file. Opening the file infects your computer with a Trojan horse.
4. A friends Facebook account is hacked and has sent out personalized messages telling all their friends to see this exciting new video. Opening the video requests a download that has a hidden Trojan horse that infects your computer.
1. A site offers a free download to a program or game that normally costs money. Downloading the pirated version of a program or game allows you to illegally use or play it, however, during the install it also installed a Trojan horse onto the computer.
2. A popular screen saver website has become infected or uploaded infected screen savers. Downloading the screen saver to your computer also installs a Trojan horse onto the computer.
3. You receive an e-mail that appears to be from a friend asking you to view this fantastic new program or look at a file. Opening the file infects your computer with a Trojan horse.
4. A friends Facebook account is hacked and has sent out personalized messages telling all their friends to see this exciting new video. Opening the video requests a download that has a hidden Trojan horse that infects your computer.