There are two parts of a computer system, hardware and software, and a CADD system is no exception. Computer hardware is the physical components of the computer such as system unit, monitor and plotter. Computer software is the program that determines the application of a system. Mainframe computers have a lot of data processing power and their size is quite big. A single mainframe computer performs all the data processing and is accessed via terminals connected to it.
Minicomputers are smaller versions of mainframe computers.
The system software manages the internal operations of the computer. It is also used to manage the electronic files in the computer. The application programs are tools that help you accomplish your work, such as designing, drafting, rendering, word-processing and project management. There are hundreds of application programs available for almost every profession. A basic understanding of the operating system is important while working on a computer.