A computer is a complex machine that is capable of performing huge computations at an extraordinary speed. Its processing power is often compared to that of a human brain. Although human intellect is the undoubted winner in this competition, the capabilities of a computer cannot be underestimated. This complex machine, influenced from the design of a human brain, mainly consists of a processing unit, an arithmetic/logic unit, computer storage, and input and output devices along with its peripherals. It is these 'parts' that make the 'whole' system. So, let's take a look at the major parts of a computer.
Central Processing Unit (CPU): Also known as the computer processor, the CPU is an electronic circuit that executes computer programs. The primary responsibility of a computer processor is to execute a sequential set of instructions that constitute a program. CPU operation can be divided into four basic steps, namely, fetch, decode, execute, and writeback. During the 'fetch' step, the processor retrieves program instructions from memory. In the decode step, the instruction is broken down into parts. The instruction set architecture of the CPU defines the way in which an instruction is decoded. In the 'execute' step, CPU performs the operation implied by the program instruction. During the 'writeback' step, the CPU writes back the results of execution, to the computer's memory.
Motherboard: A computer motherboard consists of sockets in which microprocessors are installed, memory slots, a chipset that acts as an interface between the CPU bus and the peripheral buses (a bus connects all the internal parts of a computer), non-volatile memory chips housing the system's firmware and a clock generator, which helps in the synchronization of various system components. Some motherboards also include logic and connectors to support input devices like PS/2 connectors for a mouse and keyboard.
Hard Disc: A hard disc is described as a part of the computer disc drive, which stores data and provides computer users with quick access to large amounts of data. A hard disc is an electromagnetically charged surface or set of discs that record data in concentric circles known as tracks. It is a non-volatile storage device that stores digitally encoded data. A head, resembling a phonograph arm, is used to read and write data onto a hard disk. The hard discs of desktops are generally capable of storing 120 GB to 2 TB of data. Laptop hard disc drives are smaller and have lower data storage capacities.
Computer Memory: It refers to those components of a computer, which retain digital data. It forms the core of a computer and makes up the basic computer model in collaboration with the CPU. Magnetic drums and delay lines used as primary storage by computers of the early days, have metamorphosed into a miniature silicon chip, which can achieve efficient storage of large volumes of data. Random Access Memory, popularly known as RAM, is a small-sized light and volatile form of computer memory. It is capable of temporary storage of data. Registers located in a computer processor are the fastest forms of computer storage. The most frequently used information is duplicated in the processor cache of a computer, thereby improving its performance. Computers require a non-volatile primary storage to read large programs. This non-volatile memory is known as ROM or Read-only memory. It also contains the startup programs used for bootstrapping a computer. Secondary storage media such as flash memory, magnetic tape, punch cards, and zip drives and tertiary storage media like tape libraries are also a part of computer memory.
Monitor: A visual display unit, as it is called, is an electrical equipment that displays images generated by the video output of a computer. Monitors of the early years used CRT technology for imaging, while modern computer monitors use LCD or even plasma screens. The display provides computer users with an instant feedback in the form of text and graphic images. Monitors are the most-used output devices of a computer.
Keyboard: A keyboard is regarded as an input device for a computer. With respect to the arrangement of keys, a computer keyboard is similar to a typewriter. The keys or buttons act as electronic switches or mechanical levers with characters printed on them, with each keypress corresponding to a written symbol. A keyboard has its own processor and circuitry, which consists of a key matrix, which helps bring about the keyboard operation.
Mouse: A computer mouse is a pointing device that detects two-dimensional motion. Apple's Macintosh was the first successful mouse-driven computer. A mouse translates the motion of your hand into signals that a computer can recognize and respond to. There are three basic types of mice, namely, mechanical, opto-mechanical, and optical. Mechanical mice have a rubber or metal ball that can roll in all directions. Mechanical sensors in the mouse detect the direction of motion of the ball. Opto-mechanical mice differ from mechanical mice, in that they use optical sensors to detect motion. Optical mice, popularly used today, have a laser to detect movement of the mouse. They do not have mechanical moving parts and possess higher performance speeds.
Perhaps the most important part of a computer is the 'intelligence' embedded in it. Can its computing capabilities beat human intellect? Will computers be able to replace human beings? Although nothing can be said right now, we must not forget that human intelligence is God's creation, while computers are the brainchild of a human.