The document describes the main parts of a computer including the hardware, software, central processing unit, motherboard, peripherals, and keyboard keys. It explains that the hardware refers to the physical components while the software refers to the instructions needed for the computer to function. It provides details on different types of peripherals for input, output, input/output, storage, and communication. It also describes the functions of some common keyboard keys such as Esc, Tab, Shift, Ctrl, Alt, and Enter.