Do you get those annoying phone calls from some Asian call centre advising you that your computer is faulty and as a Microsoft Centre these people can help you fix it?
It's a scam by the way, let's get that out of the way first, Microsoft will NEVER call you to say your computer is faulty, only scammers will do so. Well, you've had a call from these scum and they want access to your computer and they can do this remotely, all you need to do is (usually) visit a website and allow them to take control of your computer. Only snag is, unlike genuine remote support people, the only reason they want access to your computer is so they can infect it or lock things so you cannot use your computer again without paying them a sum of money (Often quite a large amount of money).
Don't allow them access to your computer but do take their details as Microsoft want their info to prosecute them! Take their details and fill in the Microsoft Scam Survey form and help limit the amount of money these scammers can get.