A personal computer is made up of multiple physical components of computer hardware, upon which can be installed a system software called operating system and a multitude of software applications to perform the operator's desired functions.
Though a PC comes in many different forms, a typical personal computer consists of a case or chassis in a tower shape (desktop), containingcomponents such as a motherboard.
Types of Hardware
The motherboard is the main component inside the case. It is a large rectangular board with integrated circuitry that connects the rest of the parts of the computer including the CPU, the RAM, the disk drives (CD, DVD, hard disk, or any others) as well as any peripherals connected via the ports or the expansion slots.Components directly attached to the motherboard include:
The central processing unit (CPU) performs most of the calculations which enable a computer to function, and is sometimes referred to as the "brain" of the computer. It is usually cooled by a heat sink and fan.
The chip set mediates communication between the CPU and the other components of the system, including main memory.
RAM (RandomAccess Memory) stores resident part of the current running OS (OS core and so on) and all running processes (application parts, using CPU or input/output (I/O) channels or waiting for CPU or I/O channels).
The BIOS includes boot firmware and power management. The Basic Input Output System tasks are handled by operating system drivers.
Internal Buses connect the CPU to various internal componentsand to expansion cards for graphics and sound.
The north bridge memory controller, for RAM and PCI Express
PCI Express, for expansion cards such as graphics and physics processors, and high-end network interfacesPCI, for other expansion cards
SATA, for disk drives
AGP (superseded by PCI Express)
VLB VESA Local Bus (superseded by AGP)
ISA (expansion card slot format obsolete in PCs, but still used in industrial computers)
External Bus Controllers support ports for external peripherals. These ports may be controlled directly by the south bridge I/O controller or based on expansion cards attached to the motherboard through the PCI bus.
Input and output peripherals
Input and outputdevices are typically housed externally to the main computer chassis. The following are either standard or very common to many computer systems.
• Text input devices
• Keyboard - a device to input text and characters by depressing buttons (referred to as keys or buttons).
• Pointing devices
• Mouse - a pointing device that detects two dimensional motion relative to its supportingsurface.
• Optical Mouse - uses light to determine mouse motion.
• Trackball - a pointing device consisting of an exposed protruding ball housed in a socket that detects rotation about two axes.
• Touchscreen - senses the user pressing directly on the display
• Gaming devices
• Joystick - a control device that consists of a handheld stick that pivots around one end, to detect anglesin two or three dimensions and reports its angle or direction to the device it is controlling.
• Game pad - a hand held game controller that relies on the digits (especially thumbs) to provide input.
• Game controller - a specific type of controller specialized for certain gaming purposes.
• Image, Video input devices
• Image scanner - a device that provides input by analyzing images,printed text, handwriting, or an object.
• Web cam - a video camera used to provide visual input that can be easily transferred over the internet.
• Audio input devices
• Microphone - an acoustic sensor that provides input by converting sound into electrical signals.
• Printer - a device that produces a permanent human-readable text of graphic document.
• Speakers - typically a...