There is a great difference between a laptop and desktop computer. Anyone just looking at the two would be able to tell that. The laptop can come with you, where the desktop computer is pretty much stuck on the desk. Laptops are not fixed to laptop tables. Also, the desktop computer is a lot bigger, with different parts. The laptop is a smaller, all-in-one machine. That is all very superficial, of course, so what differences are significant?
Let’s start with the desktop. It has four separate parts: the monitor, the computer tower, the keyboard and the mouse. Since they are different, you can pick and choose which of each you want. Often, when people buy a boxed desktop with everything included, they find the keyboard is of shoddy quality. They may also want to upgrade to a larger monitor screen. Then they see one of those ergonomic mouses and think they must have it. Some people buy their components separately to begin with. But it doesn’t matter; it is a mix and match system. This means everyone gets exactly what they want.
With laptops, you get what you get. You can get a wireless mouse and separate keyboard if you want to, but then you will have more stuff to carry around in your laptop bag. That reduces the laptops main advantage, its portability. There simply are not, and could never be, as many options with a laptop as with a desktop.
As far as performance, the situation is the same. Desktops can be easily upgraded to a higher memory, higher graphics card, even a better processor. A laptop upgrade often involves a professional and a large bill. Even then, there is only so much hardware that you can fit in a laptop. There are not the same restrictions on a desktop. You can turn an inexpensive desktop in to a high end performer with a little money and a little work. With a laptop, what you get out of the box is pretty much what you are stuck with.
Then, there is the cost. Desktops win hands down here, too. You can get a high end desktop computer for the price of a mid range laptop. A high end laptop with the same capacity as the high end desktop will cost you about double. You will be hard pressed to find laptops under $500, but there is a whole range of desktops in that price range. So why even bother with a desktop? The answer is simple. Portability is important. Getting work done and being connected where ever you are is a high commodity. It increases productivity and overall quality of life. Although comparing computers may make a laptop look substandard, it obviously has a huge role in the lives of many and for a good reason.