You really need this to keep your computer and documents from being damaged by viruses. Once installed, make sure the anti-virus software is set to update and check your computer automatically. It is also a good idea to regularly scan your PC for virus infections. Norton and McAfeee both provide very comprehensive security solutions but also they both use a lot of system power. If you have an older PC using either of these can significantly reduce your systems performance. AVG offer both free and pay for versions. Their free anti-virus software can be downloaded here.
Spam is unwanted email that you haven't requested. Most Anti-Virus software has an in built Anti-spam feature, and there are many stand alone Anti-Spam products available as well. Never reply to Spam email, or attempt to use the "unsubscribe" link that they usually contain, as this will only confirm to the Spammer, that your email address is a valid address and you will end up with more Spam sent to your address. As for the AV software Norton and McAfeee both provide very comprehensive security solutions but also they both use a lot of system power. A free lightweight package is available fro Comodo here
If you have a broadband connection, your computer is at risk from intrusion. A firewall prevents others from accessing your machine (and therefore your personal info). It puts a block in place and keeps your data safe. Firewalls can either be software based, such as the Windows Personal Firewall (which comes as part of the latest version of Windows XP), or hardware based (some ADSL routers have an inbuilt Firewall). If you want a free software firewall I would recommend "PC Tools Firewall Plus" rather than relying on the Windows firewall.
Make sure you back up all your data regularly and ensure your house/office is secure from thieves. Also, take care that your computer is in a safe place where it won't get wet, knocked over, or too hot.
Make sure that you regularly update your computer software with the latest security 'patches' or updates, both Operating System and applications. It is also a good idea to ensure you have the latest driver software for your installed hardware, such as video cards, network cards etc. Most software vendors and hardware manufacture's publish updates on their websites.
Spyware programs can monitor your internet behavior or copy your private data and passwords. Spyware is also notorious for slowing down computers. Install a reputable Anti-spyware package, and as with Anti-Virus software, ensure it is updated regularly. It is also a good idea to regularly scan your PC for Spyware infections.
Imagine losing all your most precious documents. The best thing you can do is to make sure you regularly copy all your important data onto CD or DVDs or an external hard drive. Online backup services are also available.
Looking after your Hard Disk could save you money, time and effort in the long term. Regularly perform preventative maintenance on you Hard Disk Drive by running a Disk Defragmentation and Disk Clean Up. This will not only ensure that your Drive remains free from errors, but could also increase the speed of your PC.
Be aware of the risks and what is happening. For example, learn a little about viruses, spam, spyware, and firewalls. Don't get paranoid or overly anxious, the internet should be fun. Just make sure you are vigilant and keep abreast of the risks.
As with most things in life, using common sense when using your PC is a good idea. Don't open any email that comes from an unexpected source, your Bank is more likely to phone you to discuss your account than email you. Never reveal your bank account details, credit card details, or computer password, unless you can be sure that the request is legitimate (if in doubt, do not give the information). And never use the CD draw as a coffee cup holder.