When computer viruses make their appearance, showing their teeth in every e-mail, instant message or USB stick, the best way to fight them is a good antivirus. But to win this fight you can’t just pick a random weapon. So what is antivirus software and what to consider when choosing one?
Definition and antivirus types: signature-based vs heuristic
Antivirus software is represented by programs specially developed in order to counter-attack computer viruses and to eliminate them out of the system. The main structure of the antivirus software is the scan engine, which has the task of finding computer viruses. In short, there are two methods of finding computer viruses.
1) signature-based detection – the antivirus software contains a database with computer virus signatures – a dictionary of all computer viruses presently known. The antivirus scans the files ont he computer, comparing their content with the virus signatures in its database; in this case, constantly updating the antivirus database is mandatory.
2) heuristic-based detection – unlike the signature-based detection, this is a proactive method because it can detect new viruses or new versions of already known viruses; this type of antivirus software works on general computer virus signatures in order to detect multiple threats: for example, a single general signature can detect a whole family of computer viruses with similar signatures.
The method mostly used is the signature-based detection. Both methods have their weak points. Signature-based detection relies on constant antivirus database updates, and if the antivirus is not updated in useful time, it is possible that a computer virus will remain undetected. On the other hand, a heuristic-based antivirus can wrongfully quarantine some programs, this type of detection being less exact.
Tips on how to choose an antivirus:
The level of protection an antivirus offers depends on its characteristics and its features – from scanning that can be manually done by the user to automatic update, real-time scanning, etc. All antivirus software offer protection as long as you use it right and you scan all hard-drives, removable media (USB sticks, external HDD, etc) and all files downloaded from the Internet, on a regular basis.
At their core, all antivirus programs have the same purpose: To protect your netbook, laptop or desktop from computer viruses through scanning and cleaning infected files. The main differences are made by the graphic interface (Graphical User Interface), the number of special function (scheduled scan, automatic update, real-time scan, etc), and the speed and accuracy of the program.
How to aquire an antivirus: you can either buy antivirus software or choose a free antivirus. Companies often offer free simplified versions or demo versions of antivirus software, which have a limited time of use (mostly 30, 60 days). Here’s what you should consider when choosing antivirus software:
- Know what kind of antivirus you’re looking for – for example, if you work on an older or slower computer, or on a netbook that doesn’t offer high performance, then you need a simpler antivirus that will use less memory in order not to slow down your computer. On the other hand, if you use the internet a lot, and access many sites, you need a powerful antivirus.
- Do some market research – look at what antivirus software is out there and read reviews about it.
- Test it – try free demo versions of antivirus software until you find the one you like.
When choosing antivirus software, you should also have in mind the following characteristics:
- Protection type – a good antivirus will offer protection against most malware: from computer viruses to worms, trojans and spyware.
- Efficiency – usually, antivirus software is tested by professional reviewers, in order to determine its efficiency. Following these tests, a top of the best antivirus software is made, and every antivirus program gets a score. These reviews can be useful when choosing an antivirus program.
- Simplicity – the antivirus software you choose has to be intuitive and easy to use in order to not give you too much of a headache and to do its job even when you’re not thinking about it.
- Additional features – features like scheduled scans or automatic update, can take some weight off your chest.
- Updates – An antivirus that doesn’t update in useful time is inefficient, so having one that has an automatic update feature would make for the best option.
a) We don’t recommend using more than one antivirus program on a computer, because system vulnerabilites will appear. Instead of eliminating malware threats, the antivirus programs will bump into each other and will not work properly.
b) If you don’t have a complete antivirus solution, you could also use an online antivirus. This represents an online solution offered by antivirus manufacturers, which scans your computer for free when you are connected to the Internet. Unfortunately they rarely offer features like cleaning and repairing files, therefore they usually work as diagnostic tools.