Small Form Factor (SFF):
Small form factor (SFF) computers are housed in smaller cases than typical desktop computers. While the term has no exact definition, it generally includes cases designed for motherboards smaller than the standard ATX small factor. It generally excludes rack-mount cases, blade servers, and industrial computers, which are designed for data centers and factory use, rather than home and office environments. Their shapes vary from cubes to mini-towers to shallow flat cases resembling home theater components.
Desktop:
A desktop computer is a personal computer in a form intended for regular use at a single location, as opposed to a mobile laptop or portable computer. We have a wide range of desktop systems.
Laptop:
A laptop computer, also known as a notebook computer, is a small personal computer designed for mobile use. A laptop integrates all of the typical components of a desktop computer.
Server:
A server is a computer program that provides services to other computer programs and their users, in the same or other computer. The physical computer that runs a server program is also often referred to as server.