Nowadays more and more people are using a computer. A lot of them use it at their work place, but an increasing number of computer users have also discovered need to have a computer at home. At same time number of Internet surfers increased. This is a good thing because people are realizing advantages offered by world of technology. As soon as they discover this, they start using computers and Internet more and more, but at same time not considering threats that are coming in from all sides. They should know that if you don’t protect yourself, nobody will. These threats are now coming from everywhere and they are growing in number and complexity. First threats of this kind were viruses. At first, viruses were not that harmful. They were designed to perform a simple task, like flashing a single message onto user's computer screen. Also spread rate was slow, because not many people were connected to Internet. But now majority of viruses are programs intentionally written to obstruct with, or harm other programs or computer systems. And they are spreading very fast.
Many companies and people have had a lot of troubles because of these viruses. And so need for antivirus software was born. At first one very simple antivirus appeared and this was enough. Now, as threat is growing antivirus software are becoming a lot more complex. Some of them have also included a firewall so to better protect users. In order to increase competition, other antivirus software producers have also come up with a wonderful idea: to offer free scan online. This was a big help for people that are frequently using a computer mostly for their personal use, meaning it is not attached to a network and uses Internet only from time to time. Now, they don’t have to spend a lot of money to buy antivirus software that will be used very rarely.
Most of these antivirus programs have to be bought in order for you to use them at their full capacity. Also you have option to test a so called “free trial version”. These trial versions include all or most of software’s features, and are available to be checked out by user for a short period of time, usually 30 days. After these 30 days, program can no longer be used. Other antivirus software producers use another method; they offer a free trial version that you can keep forever. But it is not fully operational, meaning some of options of program cannot be used as they are not activated. After you have tried a program and you consider it is fit for your need, then you’ll have to buy it to protect your computer at its full capacity.
Lately, viruses are mostly spread through e-mails because this is most common use of Internet. Also, e-mail viruses are easier to develop. E-mail viruses make use of ability of having macros or scripts implanted in word documents, spreadsheets, HTML pages, and are programmed to run when document is opened. But how does an e-mail virus works? When an e-mail with an infected document or program is received, user unknowingly opens a document/program, which in turn executes a code to open e-mail directory and to send a copy of itself as an e-mail attachment to a certain number of addresses. Some of recipients of e-mail open its attachment and process repeats itself.
This is where antivirus program comes in. This program is set to check all incoming and outgoing messages and their attachments. If an e-mail is detected to have a document or program infected with a virus program offers several possibilities to deal with threat: delete e-mail, put it in quarantine or try to disinfect it. Most of times, these choices are left to user’s decision. It is up to user to set program in such manner to best fit his needs. But not all viruses are coming by e-mail. A few of them use security errors in operating system or your Internet browser to be launched automatically. But if you keep your antivirus and all other programs updated, there will be a small chance of being infected via this route.