Antivirus programs are used to prevent, detect, and remove malware, including computer viruses, computer worms, trojan horses, spyware and adware.
However, it is possible for a computer to be infected with new malware for which no signature is yet known. To counter new threats, generic signatures can be used, can
identify new viruses or variants of existing viruses by looking for
known malicious code, or slight variations of them, in files. Some
antivirus software can also predict what a file will do by running it in
an isolated section of the computer and seeing what it does to determine if it does any malicious actions.
No matter how useful antivirus software can be, it can have problems. Antivirus software can certainly slow down a computer , this is especially important if the computer is short on random access memory.
Inexperienced users like me have trouble understanding the prompts and
decisions that antivirus software presents us with. An incorrect
decision may lead to a security breach.
If the antivirus software
employs heuristic detection, success depends on achieving the right
balance between false positives and false negatives. False positives can be as destructive as false negatives Antivirus software generally runs at the highly trusted kernel level of the operating system, creating a potential avenue of attack.
Another problem is that some malware can detect what antivirus program is being used and present you with what appears to be a warning from it, but is actually a virus that it wants you to download.
Eternal vigilance in necessary; think before you act.
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