There are different types of computer for different purposes.
Desktop is a computer which is kept on desk. It is big in size. All the basic parts are attached with the help of wires.
Desktops are kept at one place. They cannot be carried from one place to another for work. More information of Computer Click here.
Laptop is a small computer that can easily fit on your lap. You can carry a laptop from one place to another. It is wireless. It works with the help of batteries that can be charge with electricity.
Palmtop is even smaller than a laptop. It is so small that it can fit in your palm.
You can easily carry it can even fit in your packet.
All these computer are called Pcs. PC stands for Personal Computer. They are made in such a way that it can be used only by one person at a time.