It doesn't take long for a PC to fill with unwanted programs: depending on who you believe, a brand new PC will be infected with malware within 4, 7 or 8 minutes, before you get it out of the box or before you even get it home.
While some of the threats are massively overhyped, malware and other online problems are extremely irritating and, in many cases, major time thieves. These apps will keep you and your PC happy.
Avast Free antivirus
Avast is one of the most downloaded programs of all time, with good reason: it offers effective anti-virus protection without slowing your PC to a crawl or making you install security modules you're unlikely to ever need.
The free version doesn't have all of the security features of its paid-for siblings, which add anti-spam and phishing protection, but it covers the basics brilliantly and can remove unwanted browser add-ons.
Lavasoft's malware protector Ad-Aware has been on our essentials list for years, and once again the free version offers more than enough security features for everyday PC use. The main attraction here is Ad-Aware's superb anti-spyware protection, which can find malware and adware and banish it forever.
There's something of an arms race going on between security firms and malware developers, but Ad-Aware's automatic updates should keep your software current and capable of spotting even the most obscure malware. The program can also protect you from fraudulent websites and dodgy downloads, and Game Mode keeps it quiet when you're gaming.
If our inbox is anything to go by, approximately 99.9% of all email is spam – and that means 99.9% of our email time is spent getting rid of it. CleanMail has a better idea: if you use POP3 mail it uses the award-winning SpamAssassin anti-spam engine to identify incoming junk mail and get shot of the lot.
It's always learning, analysing junk messages to help it become even better over time. It can whitelist specific senders so the boss's mails never end up in the bin, and it can block entire domains of known spam senders.
You may not realise it, but your surfing habits are probably being tracked by dozens of websites keen to sell you their products. These tracking cookies are not malicious, but you may not want Amazon and friends collecting your data and knowing exactly what you're thinking of buying. If not, try Ghostery – available for Google Chrome, Firefox, Safari and more. It's available for Chrome, Firefox, Opera, Safari, Android and iOS, and its job is to block the various tracking systems that attempt to follow you around the internet to sell you stuff.
You can simply install it and let it get on with its job, but looking at each site's Ghostery report is a real eye-opener: some sites have so many different trackers and advertising networks it's a miracle their pages ever load. Ghostery also tells you exactly what each company is looking at and likely to do with your data, so if you'd rather not share every click with marketers, its a must-have.
AdBlock Plus is a controversial one. Publishers of ad-funded websites say it's depriving them of income and putting their sites in danger; fans of AdBlock Plus says that if publishers didn't make ads so invasive and annoying, we wouldn't need to block them. Not only that, but AdBlock Plus automatically blocks sites known to serve malware, so it keeps you both safe and sane.
It also features a URL typo corrector, ensuring you don't accidentally visit malware sites with vey similar names to famous brands.So if you want to control what kinds of content appear on web pages, adding Adblock Plus to Firefox, Chrome, Opera or Internet Explorer can make the web a much quieter place – and its Acceptable Ads list means you can whitelist the sites that don't go out of their way to yell at you.
LastPass Password Manager
We know that our passwords probably aren't tough enough – although at least we don't use the UK's favourites, "123456" and "password" – but remembering unique passwords for stacks of sites and services is a nightmare. Thank heavens, then, for LastPass – available for Firefox, Google Chrome and more.
LastPass creates a vault for your passwords and bank cards, generating really strong passwords and recalling them when you need them. It syncs via the cloud, too, so it's available not just in your browser but on your phone or tablet too. It even generates one-time passwords for logins you don't intend to use again or sites you're not sure you can trust.
Hotspot Shield VPN
Sometimes other people's networks just aren't good enough. Your ISP may block perfectly legal websites with overzealous filters, the site you want to see might use geotagging to lock out people from particular countries, or you might be in a coffee shop where you're pretty sure the Wi-Fi hotspot isn't secure enough to make online banking a good idea.
Enter Hotspot Shield, a virtual private network (VPN) that can disguise your real IP address, secure other people's hotspots, bypass censorship and make your own internet connection more secure. That makes it a useful tool for protecting both your privacy and your computer. The free version is ad-supported, but you can pay for an ad-free version if you prefer.
Software developers need to feed their families, we know, but sometimes their attempts to earn a few coins are way over the top: if you've ever installed a trial program and discovered it's stuck another eleventy-three unrelated and unwanted programs onto your PC, you'll know exactly what we mean.
Unchecky prevents that from happening and ensures that when you install a minor app you won't suddenly find your home page and default search engine have changed. It's available for any Windows from XP onwards, and if you install a lot of demos, you'll soon be shouting its praises from the rooftops.
Most of us have some things on our PCs we don't want others to access: our finances, perhaps, or our disturbing fan fiction about Simon Cowell and Louis Walsh. Even when you think you've safely deleted sensitive files, that's not necessarily the case.
Because if you're using public computers or selling a PC and need to be sure that your sensitive data is deleted, emptying the Recycle Bin doesn't cut it: all that does is hide the files and tell Windows it's safe to overwrite them when it needs the space. Recovering those files is a doddle unless you use a proper file eraser such as Eraser, which thoroughly overwrites deleted files and destroys them properly, keeping your private files private for good.
Kaspersky Lab's WindowsUnlocker exists to fight one of the most awful kinds of malware: ransomware, which locks up your PC and threatens to keep you locked out - or worse, to delete your files - if you don't pay a ransom. It's a growing problem, but it's easy to ensure your PC won't become a victim: just download and install WindowsUnlocker to keep the bad guys out.
If it's too late and a stranger's already demanding money with menaces, the same firm's Rescue Disk 10 acts as an emergency locksmith, getting you into your PC from a CD/DVD or USB device. Don't give up and pay the ransom – Kaspersky's software can get you out of trouble.