Microsoft will release Windows 8 later this year and it’s slated to be the biggest shift in how Windows works since its introduction in 1985.The changes will affect everything — how applications look, how they work, how they share information, even how you get applications. With Windows 8, Microsoft hopes to fix what is broken after almost 30 years of patchwork improvements.The consumer version of Windows has had about seven major releases prior to the expected fall release of Windows 8. Each of those releases built upon the prior, which is like remodelling your house seven times over thirty years. Each remodel had a purpose and a point and was generally successful, but it is easy to imagine that if torn down and redesigned from scratch it would be a very different house.In future columns I will cover some of Windows 8’s mobile improvements, visual changes, and enhancements for touch screens, however, today I want to focus on why Windows 8 will make PCs much more useful, practically overnight.One of Window’s strengths is that millions of developers create applications for it, some free, some not, some great and many horrible. But with so many choices someone has probably written the perfect application for your needs. Excluding the obvious big names like Microsoft, Google and Adobe, the problem is, there is no way to download an application from the internet and safely try it, without risking a virus infection. So while there are millions of developers creating applications for Windows, cautious computer users should shy away from the vast majority of them.So how did we get so much unusable potential and how does Windows 8 unlock it?When personal computing began in earnest in the 80s Microsoft rightly assumed that if someone had physical access to the computer they should have access to view every file and run every application. Computers were not connected to the internet then, nor were they part of the family life, so it was reasonable to think that whoever used the computer should have carte blanche access. Furthermore, any application run on the computer could be trusted to do whatever it wanted.Since then, computers have migrated from basements and garages, to living rooms and bedrooms, and are connected to the internet. To keep up, Microsoft’s remodels included ways for family members to keep files separate from each other. Recently, Microsoft introduced different types of user accounts, with different levels of access in another attempt to limit who can do what.While the notion of who can access what has evolved, the same advances haven’t been applied to which application can do what. For example, should a game you just downloaded off the internet have access to your e-mails? Or your camera? Today they have access to everything — which is why viruses are so effective and devastating. Once they get running on your computer they basically have access to e-mails, documents, other applications, your camera, microphone — anything on or connected to your computer.And this is why all the applications, written by the millions of developers are unusable, because Windows grew from the premise that all applications can do whatever they like, and so we are too scared to download anything from the internet in case it wants to do evil.Windows 8 fixes this by moving to an iPhone app-like model. New applications built specifically for Windows 8 will be called Metro apps and can only be bought from Microsoft’s app store (many will be free). Microsoft’s app store will clearly list all of the things each application will use — things like the microphone, camera, network etc. It is Windows 8’s job to make sure that even if they try, the applications only get access to what they state in the app store. And, applications can only access their own data, so a virus would not be able to get to your e-mails, or Word documents.The great outcome of this move by Microsoft is that not only will computers be safer, but we’ll be able to do more safely with them. Instead of making them more secure by crippling different features, Microsoft has found a way to carefully control access without burdening the user. By creating the app store, users will be able to find applications and safely try them, unlocking the potential of millions of applications practically overnight.Paul Coleman is a software developer for Orbis Investment Management Limited.