How antivirus program protects your computer, antivirus types

Antivirus software detects and deletes viruses from your computer and provides its further protection. All specialized programs for protection from viruses can be divided in several types.

Types of antivirus programs

  • detectors;
  • doctors (fags);
  • auditors;
  • doctor-auditors;
  • filters and vaccines (immunizators).

How antivirus program protects your computer

type antivirus

Detection software

Detectors allow to detect files infected by one of the known viruses. These programs check if there is a specific byte combination for given virus in files from selected storage disk.
It should be underlined that detection software can detect only «known» viruses. Some detection software can be adapted for new virus types, it just needs to be customized with new virus byte combinations.
The most part of detection software has «doctor» function, i.e. they try to recover infected files or disk spaces to its initial condition. As a rule, the files that have failed to be recovered, become crufty or are being deleted.


Auditors have two working phases. At first they memorise the information about program and system disk spaces (boot sectors and table partition sector) condition. It is expected that in this moment programs and disk system control areas are uninfected. Upon that it is possible at any time to compare program and disk system control area condition with the initial one, with help of audition software. The user is being informed about any detected mismatch conditions.


Filters are host-based in the computer random access memory, they listen the addressings to operating system that are used by viruses for multiplication and spoiling, and they inform user about it. The user can accept or deny the required operation execution.
However, advantages of filtration software usage are significant enough — they allow to detect many viruses at their earliest stage, when the virus has not managed to multiply or spoil anything yet.


Vaccines upgrade programs and disk in such a manner that it is not reflected in program functioning, but the virus, that is being vaccinated, considers these programs and disks as already infected.
Besides, it is also necessary to note the following: no one existing antivirus technology can provide full protection from viruses; antiviruses can detect the threat where it doesn’t exist; antiviruses download upgrades from the Internet, and therefore they expend the traffic, and many others. However, in spite of these disadvantages, the necessity for antiviruses is completely obvious, and it will never hurt your computer.