Basically the computer attacks come from two sources, they are the network virus and local virus. The attack is an attack that utilizes a network connection among computers as the main media. Usually the attacker collects system data when the victim is connected to the network. Another method is to plant a small program into the system when the victim does not use the network (Internet), and the small program will be active when an Internet path is opened.
Local attacks can come from the media connected to PC, such as floppy disks, CDROM, or flash disks, memory cards and the like. these attacks can be a virus, worm or a root kit. in order to be clearer, here are some types of attacks that often come to the PC.
Virus
Perhaps most readers already know the villain. Virus can spread and breed as fast as possible because of The Internet. It took a few months for the virus to spread. But now a newly created virus can spread within a few hours. In addition, through the Internet, viruses are also great to duplicate of various storage devices such as floppy disks, Flash drives, CD-ROM, and memory cards. The virus itself is also composed of three types, namely, the viruses of file, the virus of the partition, and the viruses of network. Files and the partitions are the oldest virus, meanwhile a network virus which is a newcomer is specially created to paralyze the computer network.
Spyware
Although the level of risk is much lower than viruses, spyware continues to be cautious. The reason is that an attacker can steal sensitive datas on your computer unwitting victims. So don’t be surprised if your e-mail address or credit card numbers are stored on your hard disk may change hands without your knowledge. Internet line is the primary means of planting spies. Spyware is important to note because according to independent research institute IDC, 60% PC connected to the Internet in 2004 had been infected with Spyware. While the U.S. Federal Bureau of Investigation (FBI) found that 80% of disturbances arising on the PC in 2005 caused by Spyware.
Worm
Unlike a virus, worm is a small computer program that can be spread without having to ride on a particular file (an independent). The distribution media is also still using the network, both local and Internet. Some worms are created to disable a network, but some are made to retrieve the data and delete files. The good news is this worm could be prevented by an updated anti-virus programs. Or by relying on the patch program made by the operating system manufacturer. but patches often come longer than the speed of the spread of worms.