The problem with Windows, is it was built on a garbage base. While that base has been improved over the years, it is still an unsound base. Much of the underlaying code is still the same - to maintain compatibility as much as possible. I had to buy a new desktop a year ago. It came with Windows 7 and I have probably had over a thousand updates since, about 85 - 90% being Microsoft security updates - I don't think I had that many on XP over 10 years of use. I also use Ubuntu and a couple of variants. I have not had anywhere near the high percentage of security updates as I have had on Windows. The Linux/Unix base is much more secure and tougher to break than the Windows base. If you are going to "break into the system", it would have to be through some application - e.g., Java. IBM mainframes have always been quite secure. I remember 2600 magazine, publishing an article, attempting to hack into IBM's VM system a few years back and could not do it. If you ever developed or worked on an operating system kernel (or a database), you would get a glimmer of what it takes to try and hack a well defined and crafted OS.