yes depending on the computer
yes
If Minecraft is not running, no it will not slow your computer down.If you have a low end or older computer then playing Minecraft may slow it down a little as it's a fairly hardware intensive game. Just give it as much ram as you can and turn the graphic details down until your happy with it.The Minecraft WiKi has a lot of information on managing the game.
it is when computers come with pre-installed programs that slow down your computer.
probably because its an old program. Minecraft is slow on many computers because of the language it is written in- Java. Java is an interpreted language, so it often runs slower than other programs would. The advantage of using java, though, is that it runs on more computers because it is cross-platform. It isn't really slow. if u are having problems with speed its your computer
yes
minecraft pe is slow
It can slow your computer down a little but with most computers today you'd never notice.
Yes, Minecraft is readily available for computers on their website.
It will while the program is running, but after it stops running there will be no change in computer speed.
No,visiting websites even when they set cookies or store temporary files don't slow computers down. if a website exploits a security flaw it could execute code that would slow down a computer.
It should be up to 10 computers although speed will drastically slow down with extra computers added.
No, but Minecraft does work on Macs.