Basic security against computer viruses and spyware doesn't have to cost a fortune – and it's the No1 must for any PC owner.

You can find many good applications available for free on the internet. We've picked out a few of the best below.

For most home users, these will suffice in keeping a basic level of bugs at bay.

To gain an even higher level of protection, and additional security options for example against spam email messages, you will need to upgrade to a paid-for service or off-the-shelf boxed product.

But if the worst strikes and you do get a virus, that's what our Agents are here for. Just give us a call for help and advice.

Remember though, if you sign up to our Geek Squad Tech Support membership for £6.99 a month, you get free anti-virus and spyware protection included as part of the package.

Avast – It might sound a bit like pirate speak, but Avast is very highly regarded.

So long as you're using it on a personal PC (not for business) you're allowed to use the free version, which offers virus and spyware protection, email scanning, infection from 'chat' sessions and attacks from hijacked web sites.

What you don't get though is fast updates, the ability to browse suspicious web sites (but you should never even risk it), spam protection (use Gmail instead) or protection from hacker attacks (make sure you keep your browser up-to-date to try and prevent this).

http://www.avast.com/free-antivirus-download

AVG Anti-Virus Free Edition - – One of the most popular free packages, this a slimline version of a full-blown paid-for suite with a lot of bells and whistles. You don't need most of that so if you know how to use your PC sensibly, this provides good basic protection.

Features include an online link scanner, protection from viruses and spyware, and automatic updates.

You don't get features like phishing protection, though many modern browsers and search engines already offer this for you. There's no firewall either but Windows has one built-in and your Internet Service Provider may also offer one.

http://free.avg.com/gb-en/homepage

Windows Defender - Microsoft's own free security software protects PCs from pop-ups, spyware and unwanted software.

It's not anti-virus software in itself, but if something online does slip through the net and end up on your PC, Windows Defender should hopefully be able to detect and remove it.

http://www.microsoft.com/windows/products/winfamily/defender/default.mspx

HouseCall - From Trend Micro, this downloadable programme can scan your entire hard drive and detect if you have any problems with viruses and spyware.

It won't protect you but it's a useful tool to help you become aware of the latest threats.

http://housecall.trendmicro.com/uk/?id=home

ZoneAlarm - This free firewall is a powerful tool considering it doesn't cost a penny. It can monitor all inbound and outbound web traffic and alert you to potential threats from hackers.

There's also a free Spyware protector on the Zone Alarm website too.

http://www.zonealarm.com/security/en-us/free-upgrade-security-suite-zonealarm-firewall.htm