How to Recognize Trojan Horses, Viruses, and Worms
A computer virus is the type of computer program that is hidden in other program to produce its copies in other locations of hard drive. It performs a malicious action like creation of clusters and data destruction. There are many types of viruses and worms that affect computers in various ways. However, common categories of computer viruses are worms and macro virus. Computer viruses are not naturally generated as they are man-made products. Once these viruses are created, they are released on internet as their spread is not under control of human.
Macro viruses: Micro virus is the sort of code that is usually embedded in the data files. Some spread sheet and word processors programs like Microsoft excel and Microsoft word permit you to attach macro with created documents. In this way, these documents customize and control the programs that create or extent the macro viruses program. For instance, a document attached with macro may execute whenever you save it and it can run external spell checking program to generate error in the text.
Stealth viruses: An active stealth virus makes modification in files or boot records and then hides them. It performs this task by monitoring the functions of the system that is used to read sectors and files from storage media. Sometimes the modification of stealth virus remains undetected for antivirus programs. If you want to eliminate it, the virus must be existed in memory at the execution of antivirus program.
Polymorphic viruses: It produces various operational copies in the system that is undetectable for virus scanners. One way of eliminating Polymorphic virus is performed through self-encryption with the use of variable key. Some sophisticated type of polymorphic virus can change the sequence of instructions. A simple virus scan program cannot identify and remove the infection of this virus. It requires sophisticated scan engine to search and eliminate it.
Boot sector viruses: Boot sector virus infects their own code in dos or master boot record of the computer. Master boot record is the small type of program that runs at the start up process of a computer. It monitors the boot sequence and decides about the computer partition from the boot. Boot sector virus is very dangerous as it infects hard drive easily. You need a bootable antivirus disk to remove boot sector virus from your computer.
Worms: Worms work like viruses that generate functional copies in computer through network connections. It infects the normal use of the pc and it is tough to remove them because they exist as separate items. Worms have too many similarities with viruses so they are also referred as viruses.
Trojan horses: The name of Trojan house is kept on the image of wooden horse founded in Greeks. Trojan horse virus is the type of program that affects the speed and performance of the computer. Some people regard it replicating malicious programs as it infects numerous harms to their computer. There are different types of Trojan viruses and there is always need of reliable antivirus program so that your computer can save from the infections of these viruses.