VarunSingh wrote:
But we can install and run Mac OS in other laptops. So, are you saying Apple computers do not permit any other hardware to run Mac OS?
Apple's End User License Agreement (EULA) specifically only allows running OS X on genuine Apple computers. It is therefore illegal to run Apple's software on ordinary OEM laptop including those of Dell, Sony, HP, etc.
The only sort of exception to this rule has been the ModBook Pro - see http://www.modbook.com/modbookpro and the Savant who make a home control/media system use a Mac mini as the guts of their Host Controller. In both these cases they buy genuine Macs and rip the guts out and put them in their own custom cases, it is still therefore a case that they are running OS X on genuine Apple computers.
It is not technically impossible to run OS X on non-Apple computers, it is more difficult than on a real Apple computer, but it is the fact it is illegal that is the issue. Microsoft specifically license Windows to be allowed to run on pretty much any make of computer, Apple do not.