A PC or Personal Computer is a machine that can be instructed to carry out sequences of arithmetic or logical operations automatically. Computers have the ability to follow generalized sets of operations, called programs. These programs enable computers to perform an extremely wide range of tasks. A computer, including the hardware, the operating system (main software), and peripherals required for operation can be referred to as a computer system. Conventionally, a modern computer consists of at least one processing element, ie. a central processing unit (CPU) in the form of a metal-oxide-semiconductor (MOS) microprocessor, along with some type of computer memory, typically MOS semiconductor memory chips. The processing element carries out arithmetic and logical operations, and a sequencing and control unit can change the order of operations in response to stored information. Peripheral devices include input devices (keyboards, mice, etc.), output devices (monitor, printers, etc.). Peripheral devices allow information to be retrieved from an external source and they enable the result of operations to be saved and retrieved. We can learn about each core parts of a Personal Computer in a nutshell.