Yes... "Welcome aboard, Captain! And by the way, that iron skillet that just smacked you in the face is perfectly normal. Please be advised that this will happen to you quite frequently during the next several weeks or months."
The Linux system is much more than "a replacement for Windows." It is genuinely very different.
It is closer to Windows-NT, and very far removed from DOS.
The biggest apparent difference between the two systems is that Linux is a loosely coupled system.
The various parts which make up the system are not tightly connected. Some people say that "they're held together with string, Scotch tape, bubble-gum and glue." Maybe so, but held-together they are!
In the Windows system, the graphical user interface (GUI) and the remainder of the system are very tightly linked. The Windows Explorer web-browser is tightly linked with that GUI-shell and Microsoft is apparently very proud of that.
Linux, on the other hand, consists of many disparate pieces. The windowing system, X-Windows (no relation...) is client-server
by design, which means that you can run a fully-graphic session against a remote computer that does not even have a video card. The window-manager, and the GUI itself, are loosely coupled even to X-Windows, which means that you can make a single computer look many different ways; the choice is yours. But the choice is overwhelming.
The various subsystems ... printing, network services, scheduler, Web services, ssh, and so-on ... are likewise independent
of one another; not
provided by "a single vendor." Remember, this is an operating system that can run on everything from the largest IBM mainframes to an Apple iPod. It is a system that can marshal together the services of a cluster consisting of hundreds of multi-processor CPUs and make them all appear as one. It really is
"You tend to understimate a cute little penguin until he's coming straight at you going a hundred miles an hour..."
-- something like that, sorry, Linus...