Hardware is the physical aspect of a computer. While computer software exists in the form of programs and procedures, hardware comprises the mechanical, electronic, and electrical components of a computer system. By definition, the different parts of a computer are included in its hardware. Computer hardware includes the central processing unit, motherboard, microchips as well as computer peripherals like input-output and storage devices that are added to a host computer to enhance its abilities. Here is an overview of the different kinds of computer hardware with pictures. Here is a list of the fundamental units of a computer along with a list of media devices, networking hardware components, and computer peripherals. They together form the set of hardware components of computers. ➺ Main Components ➺ Media Devices ➺ Networking Hardware ➺ Computer Peripherals Bus: It is a subsystem that transfers data within and between computers. The computer bus provides a logical connection between the different computer peripherals. CPUs use the control bus to communicate with other devices in the computer. The address bus is used to specify a physical address. A processor specifies the memory location it wants to read from or write to, on the address bus. The value that it needs to read or write in sent to the data bus. Thus, the data bus carries the data being processed. A parallel bus is capable of carrying multiple data in parallel while a serial bus carries data in a bit-serial form. An internal bus connects the internal components of a computer to the motherboard while an external bus connects the external computer peripherals to the motherboard.

• AGP: Short for Accelerated Graphics Port, AGP is a high-speed point-to-point channel that enables the attachment of a graphics card to the computer's motherboard.
• HyperTransport: It is a low-latency point-to-point link that uses high bandwidth and acts in a bi-directional manner. It facilitates power management.
• PCI: The peripheral component interconnect standard refers to the computer bus connecting peripheral devices to a motherboard.
• PCI Express: It is a computer expansion card interface format.
• USB: Universal Serial Bus, as it is called, acts as an interface to a host computer. It enhances the plug-and-play capabilities of a computer. USB is a popular device used today.
• QuickPath: Also known as the Common System Interface, QuickPath is a point-to-point processor interconnect that stands in close competition with HyperTransport.
• Serial ATA: It is a computer bus that enables the transfer of data between mass storage devices and the motherboard.
• Serial Attached SCSI: It enables the transfer of data from computer storage devices like hard drives and tape drives. It is a point-to-point serial protocol.

Central Processing Unit: It is a set of logic machines that can execute computer programs. The fundamental function of a CPU is to execute sequences of stored instructions known as programs. During its first step of operation, the processor retrieves instructions from the program memory. This step is known as the 'fetch' step. In the 'decode' step, the processor breaks up the instructions into parts after which it is executed. During the fourth step of writeback, the CPU writes back the results of the processed instructions into memory. Computer fan: It is attached to the CPU and is used to lower the temperature of a computer. Fans in the computer case help maintain a constant flow of air to the computer system. Firmware: It is a computer program that is embedded in a hardware device. It is midway between hardware and software. Being a piece of computer program, it is similar to software, while being tightly bound to hardware makes it close to being a hardware component. Motherboard: It is the central printed circuit board, abbreviated as PCB, which forms the complex electronic system of a computer. A motherboard provides the computer system with all the electrical connections, the basic circuitry, and components required for its functioning. Power Supply: This component is responsible for supplying power to the computer. It converts the AC power from the mains to low voltage DC power for the internal components of a computer. RAM: Short for random access memory, RAM is the physical memory of a computer. It is used to store the currently running programs and is attached to the motherboard. Sound Card: It is a computer expansion card that enables the input and output of audio signals to and from a computer. Sound cards provide multimedia applications with the audio components. Video Card: Video card that is also known as a graphics card is a hardware component which generates and outputs the images to a display. Storage Controllers: They are located on the motherboard or on the expansion cards. Storage controllers include controllers for the hard disc, CD-ROM, and other drives. Devices such as CDs, DVDs, and Blu-ray discs are some of the popular removable storage media that can store digital data. USB flash drives are a relatively recent development. Tape drives and zip drives are less commonly used while the floppy disks are obsolete. Hard discs and solid-state drives are used for internal storage. Here is a brief introduction to each of these storage media. Know all about the hard drives. Compact Disc: Popularly known as CDs, compact discs are storage devices for storing digital data. Standard CDs can store around 80 minutes of audio. CD-ROMs contain data that is accessible for reading and is not modifiable. CD-ROMs are used for distribution of computer software and multimedia applications. A CD Writer is an optical disc drive that uses laser radiation or electromagnetic waves for reading from and writing data onto discs. Digital Versatile Disc: Commonly known as a digital video disc and abbreviated as DVD, a digital versatile disc is one of the very popular optical disc storage media. With physical dimensions similar to those of a compact disc, DVDs can store data as much as six times more than a CD. A DVD-ROM drive is used for reading data from a DVD. A DVD Writer is used for reading from and writing data to a DVD. DVD-RAM drives allow data to be read and written rapidly from specific types of DVDs. HD DVD is a high-density optical disc format that succeeded DVD. Disc Array Controller: It manages physical disc drives and brings them to the form of logical units. It provides a disc cache and implements hardware RAID. Floppy Disk: It is a disc of a thin magnetic storage medium covered by a plastic shell. With the advent of flash and optical storage devices, floppies have become obsolete. Tape Drive: This data storage device reads and writes data stored on a magnetic tape. Tape drives have storage capacities ranging from a few megabytes to multiple gigabytes. They are mainly used for archival storage of data. Hard Disc: It is a non-volatile storage device that stores digital data on magnetic surfaces. It is used for medium-term storage of data. Solid-state Drive: This storage device uses solid-state memory to store persistent data. It can replace the hard disc drive in many applications. Blu-ray Disc: It is an optical disc storage media format. It obtains its name from the blue laser that is used to read and write this type of disc. Owing to its shorter wavelength, blu-ray discs can store large amounts of data. BD-ROM drive is used for reading data from a blu-ray disc and a BD writer can be used for both reading from and writing to a blu-ray disc. USB Flash Drive: It is a small-sized removable and rewritable storage device with a storage capacity ranging from 64 MB to 64 GB. Due to their high storage capacity, durability, and compact structure, they have gained immense popularity in the modern times. Know how a flash drive works. Zip Drive: Iomega came up with this medium-capacity storage media in 1994. It had a capacity of about 100 MB. Zip drives could never become standardized and were replaced by rewritable CDs. Here is an overview of some of those pieces of hardware, which make it possible for a computer to be a part of a network. Update yourself on computer networking. Network Card: It is one of the most important pieces of hardware as it allows a computer to communicate with other computers over a network. It serves as a networking medium and provides the computers with a MAC address system. A network card is also known as a network adapter, a LAN card and is better known as an NIC. Modem: This device is used for dial-up connections. It modulates analog carrier signals to encode digital information and demodulates it to decode the information transmitted. Router: Routers are not exactly pieces of hardware. Rather, they are devices that are used to join multiple wired or wireless computer networks. Know all about routers. Apart from the hardware components of a computer, there are many external devices that are equally important for its functioning. Keyboard, mouse, and the visual display of a computer form its basic input and output devices. Joysticks, game controllers, and other pointing devices are commonly used for the gaming applications on a computer. Headphones, speakers, microphones, and webcams are popularly used for running multimedia applications. Let us look at some examples of these peripheral devices. Keyboard: It is an input device, which derives its design from that of a typewriter. A keyboard consists of multiple keys laid out in a specific way. Each key acts as an electronic switch either producing a letter, number, or a symbol that is typed into a word processor, or performing a certain computer operation. Visual Display Unit: Popularly known as a monitor, it is an electrical device that displays images produced as a result of video outputs from computers. Mouse: A computer mouse is a pointing device that detects two-dimensional motion. The motion of a mouse translates into the motion of a pointer on the computer display, enabling the user to control a graphical user interface. Trackball: It is a pointing device that comprises a mouse along with a ball with sensors to sense rotational motion. Trackballs find utility in special-purpose workstations and video games. Headphones: It consists of a pair of small loud speakers, which can be held close to the ears. They can be connected to an audio-frequency source such as an amplifier or a CD player. Know more about headphones. Microphone: It is an acoustic-to-electric transducer that converts sound signals to electrical ones. Commonly, mikes consist of a membrane that vibrates in response to sound. The vibrations are translated to electrical signals. Know more about microphones. Printer: This peripheral device produces hard copies of electronic documents. It is attached to a computer by means of a peripheral cable or a USB cable. A printer is sometimes combined with a scanner that serves as a photocopier. Scanner: It is a peripheral device that can scan images, handwriting, or objects and convert them to digital images. Game Controller: It is an input device that is used to control the operations of a video game. It is connected to video game consoles or personal computers. Gamepad, which is also known as a joypad or a control pad, is a game controller with digits and action buttons. Most of the video game consoles use gamepads as input devices. Joystick: It is an input device that consists of a stick that is pivoted on a base and indicates its direction to the device it controls. Joysticks are used in video games and mobile phones. Speaker: Computer speakers are external audio devices that enable computer users to listen to audio media. Multimedia speakers consist of an internal amplifier. A speaker has a jack connecting it to the sound card. Webcam: A web camera is a small camera that is widely used with video conferencing and instant messaging services. They are digital cameras which can upload images to a web server. This was an introduction to the different kinds of hardware with examples. With the advancement in computer technology, we can look forward to the development of many more hardware components that translate technology to action!