First of all we need to set the used terms straight. You cannot compare Apple Macintosh (Mac for short) with Microsoft Windows. Apple names its computers and notebooks Mac's. A Mac is the hardware itself. Every Mac runs on Mac OS X, which is the operating system. Microsoft Windows is also an operating system, so if you want to compare operating systems only, you would have to ask to compare Apple Mac OS X with Microsoft Windows. I assume however that you wish to compare the whole picture, so an Apple Mac with Mac OS X compared to a normal PC or notebook with Microsoft Windows.
Most users use Microsoft Windows on their computer and notebook. It gets installed on most new computers and notebooks, so people grow up with Microsoft Windows really. Using any other operating system will therefore take time to get to know all the ins and outs. Microsoft Windows is easy to use on itself and is very stable. What makes Microsoft Windows unstable is most of the time bad drivers. You see, Microsoft creates only Windows and not the hardware (the computer or notebook) that it runs on. Companies such as HP, Dell, et cetera are responsible for supplying you with the necessary drivers for your computer or notebook. If you do not have a branded computer, then the individual hardware manufacturers are responsible for supplying you with the necessary drivers for their hardware which you use. These drivers very often contain bugs, which makes Microsoft Windows unstable. The same goes for third party applications, which may cause Microsoft Windows to become unstable and which may overwrite system files, leave traces in the registry when the application gets removed, et cetera. All this can make Microsoft Windows unstable and may slow it down. Since Microsoft Windows is also used so much, evildoers target Microsoft Windows more than any other operating system, since most users use Microsoft Windows, so they simply try to target the biggest crowd.
Apple does not only make Mac OS X, they also make the hardware; the Mac. They are made especially for each other. This makes them a perfect match. Mac OS X does not require any third party drivers because of this out of the box, unlike Microsoft Windows. Mac OS X, because it is designed especially for the Mac, does not consume much resources. This makes Mac OS X fast and very stable. Mac OS X is also very easy to use. It is the most easy to use operating system available. It simply works. The Mac's are all well designed and made of quality materials. Some people state that Mac's sometimes have outdated hardware, but they forget a few important points then. First of all Apple releases products according to a release schedule, so they do not release a new MacBook Pro for example every week. Since they stick to a release schedule, the value of any Mac does not decrease fast, unlike with any other computer, since new hardware is released daily and companies such as HP and Dell for example release new computers and notebooks every week, meaning that that new notebook which you just bought will be outdated in a few weeks, whereas with a Mac it may take a year of more before it is officially outdated. So if you buy a Mac now, is its hardware not outdated in half a year for example? Yes, the hardware will be half a year old by then, whereas HP or Dell for example release new models weekly so their hardware will be only one week old for example... but what people forget is as stated before how fast their computer or notebook will be replaced with a new model and more important, a Mac which uses hardware which is half a year old very often performs faster than a computer of notebook which is only just released, simply because Mac OS X is a lightweight operating system and does not demand much from your hardware. Mac OS X also does not work with a registry, meaning that removed applications do not leave clutter behind. Applications can also not overwrite system files, unlike with Mac OS X. Most viruses which there are for Mac OS X also require user interaction due to the way that Mac OS X is set up, being based on UNIX, just like Linux and BSD for example.
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