Yes you can do that, although it goes down as well. Bitcoin is very young and so its still volatile. I expect it will stabilise in time, but unless you really know what you are doing you'll probably lose money if you try to day trade. You could do what I do I just bought a bundle of them, put them in cold storage, and forget about it. I'll see what they're worth in 10 years.
Bitcoin is like any currency, it rises and falls, so you can theoretically gain money by buying lower and selling higher. Of course, Bitcoins are a generatable currency to a certain extent, so I would sooner trade physical currency that cant generated so easily.
Yes, that's exactly what it means. However there's no guarantee that the value of bitcoins will go up, even within the next month or so.
Bitcoin is not a legal tender and not approved by so many countries. Take care
yes, but it is just as likely to drop in value and you could lose money
