1. Anti-virus : Probably one of the first thing which comes into one's mind when thinking about security. An anti-virus is an inevitable tool for the security of a PC. One can either choose a paid version of the anti-virus of his choice or opt for the equally effective free antivirus. Before choosing the anti-virus, it is necessary to check whether the anti-virus has resident protection or not. Resident Protection automatically detects viruses when they are loaded into the memory and takes the appropriate action thus saving a user from sitting hours in front of the PC scanning for viruses. It is important to check regularly for updates. Also do a quick scan (scanning Windows folder, Registry, Documents and recent downloads) at least once a week and a full scan at least once a month even if your PC appears fine.
2. Anti-spyware: A spyware is a program which collects private information and sends it to its programmer. Spywares are considered more dangerous than viruses as they steal private information like Windows registration number, bank account details, credit card's information, site logins, which can be used to harm a user in all possible ways. Login Accounts to social networks like Facebook seem to be the prime target. Thus, it is necessary to have a good anti-spyware software with resident protection , registry monitoring and browser monitoring. Again it is the user's choice to either opt for a paid one or a free one. It is important to enable the automatic update function in the anti-spyware software and to do a quick scan of the PC once a week. It is also necessary do a full scan once every month for best results.
3. Firewall: A firewall prevents unauthorized or malicious applications from reaching a computer. A firewall is basically needed to protect a PC against Trojans, spyware, worms, hackers, hijackers and other known and unknown threats. However, a firewall must not be assumed an alternative to the anti-virus or anti-spyware software. Before choosing a firewall, the most important thing to keep in mind is the ease of use and the amount of customization possible. An often overlooked factor upon choosing a firewall is the amount of resources consumed by it. Keeping all these factors in mind, a good firewall software(free or paid) must be chosen. It is important to read the alerts displayed by it carefully, and select an appropriate action to do.
4. Anti-spam: Anti-spam software has become important because of the amount of spam messages received by internet users frequently. These spam messages are the most common cause of cyber crime. Installing one and using it is easy. So don't worry about how to use one. The only difficult thing is to be patient with it. Its performance will improve over time. You can download any of the free anti-spam available over the web or can opt for a paid version.
5. Windows Update: A very important aspect of PC security is updating Windows. It is necessary to enable Automatic Updates in Windows which help to get all the latest security fixes. Getting these updates will help Windows work better and will make one's working more secure.
6. Backing Up: It is important to back up all your important data to have a copy of it whenever needed in case of a virus attack. A back up comes in handy in such unexpected situations.