(1) Yes, (2) Maybe, (3) No and (4) You can't compare the two.
You're asking us to start another discussion on an age old topic which has been discussed thousands of times... PC vs MAC. You're going to get varying opinions both ways. Everyone has their preference. Obviously, your friend prefers a MAC.
Here are your questions answered in the order asked. But, keep in mind, I am a PC user and prefer to stay that way. I don't like MACs.
(1) Yes. Your friend is partially correct. Not all programs used on a PC (Windows systems) will release memory when they close and sometimes a PC must be rebooted to release it. Not all software used on a PC is that way though. I own a PC that runs all the time. The only time it ever gets rebooted is when some patch installation needs to reboot the machine to update files in use. And, I don't suffer from memory leaks like your friend has told you they all do.
(2) Maybe. The key word here being "can". Some MAC's can be up for months, some can't. It depends on how they're used and what's installed on them. I know of a person using a MAC that must reboot it a couple of times a day because it slows to a crawl. In addition, some Windows machines can be up and running for months on end, just like your friend's MAC.
(3) No. I don't know of any computer, MAC or PC that is immune to anything. They all have their good side and their bad side. Some people know how to use them correctly, some don't. Your friend is pro-MAC, so of course s/he's only going to tell you the good things.
(4) You can't compare the two. MAC's and PC's are built different. What's available for one isn't necessarily available for the other. Comparing the two is like comparing a gas powered automobile with an electric automobile. They're both forms of transportation, but they're built different. Parts that fit one don't necessarily fit the other. Mechanics who work on one don't necessarily work on the other.
Believe what you want to believe. If it were me, I would take what your friend has told you with a grain of salt. If you're currious about a MAC, then experience one yourself. If you like it, then switch. If you don't, then stay with a PC.
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