Windows 8 comes with Microsoft's Windows Defender technology built-in and offers Microsoft-vetted apps through the Windows Store. Both those changes mean that your PC has more protection built in, but they don't mean you can neglect all the other aspects of computer security. Here are the reasons why.
Before anyone starts trolling: while this post is Windows 8-specific, security isn't something you can take for granted on any platform.
1. Built-in security can't address everything
Using any form of anti-malware solution is better than taking a "she'll be right mate" approach (or the more arrogant and equally dangerous "No malicious software is going to go unnoticed by me" attitude). It's definitely better to be using Windows Defender than to be using nothing, but it's only part of the solution. You need to ensure that your machine is regularly updated with the latest patches, that you don't visit suspect websites, that you keep your passwords diverse and secure, and that you protect other connected devices. For some people, a subscription to a security suite solves some of those problems; others pull together their own solutions with free resources. But no good solution rests on a single approach.
2. Desktop apps still have a big role to play
Unless you're running a Windows RT tablet, you'll inevitably end up running "traditional" desktop apps as well. In that context, all the security issues associated with Windows arise.
3. App stores don't offer total protection
Code on the Windows Store is vetted by Microsoft, which means obviously malicious activity will be blocked. Even leaving aside the possibility of occasional mistakes, Microsoft can't stop users ignoring the permissions which are granted to legitimate apps to (for example) access your internet connection or browse your contacts. Check permissions carefully before installing anything.
4. Security matters on multiple platforms
We recently addressed a reader query about whether the similar appearance of Windows 8 and Windows Phone 8 made life riskier for everyone. The simple answer is no: the platforms have a similar approach but still require separate code. But the same rules apply to Windows Phone 8 as to its desktop counterpart: you need to take care when launching apps and visiting sites.
5. Users are the biggest risk
No operating system can entirely protect against user error or stupidity. Windows 8 does a good job of securing its environment -- arguably as good a job as anything out there -- but security will always be a work-in-progress. Be aware and take steps to minimise the problem rather than being part of it.
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