Computer hardware refers to the physical parts that contribute to a computer system. These include internal devices like the central processing unit (CPU), random access memory (RAM), hard disk drives, and graphics cards.
External hardware includes peripherals such as a mouse and keyboard. It also includes external storage devices like CDs and DVDs.
Motherboard
The motherboard connects and enables communication between the functional components of a computer, including a central processing unit (CPU), random access memory (RAM), hard disk drives, and expansion cards. It also distributes power from the power supply unit (PSU) to various parts of the system.
Motherboards have connectors for USB, SATA and other ports that allow users to attach peripheral devices like a printer or monitor. They also contain chipsets that manage data flow between the CPU, RAM and storage devices. Most feature slots for expansion cards, including graphics cards and sound cards that boost computing capabilities.
CPU
The CPU, or central processing unit, is the electronic machinery that carries out the instructions from software to make your laptop or desktop computer function. It also exists in many other modern devices like smart thermostats, TVs and even washing machines.
The CPU uses four primary functions to execute the instructions it receives from input devices and memory: Fetch, decode, execute and write back. It does this by passing input data words to its arithmetic logic unit and receiving output from memory via the control unit. The arithmetic logic unit performs integer arithmetic and logic operations on these words (called operands) and passes the result to the output devices.
RAM
RAM is a form of volatile memory that loses its data when the power is switched off or reset. It stores the information needed by the CPU for applications and processes.
RAM comes in the form of computer chips integrated on a rectangular flat circuit board known as a memory module. Computers typically come with two or more modules that can be upgraded if needed.
When you open an app or file, your system pulls it from storage and loads it into RAM. Since RAM is faster than storage, this helps your PC perform quickly.
Hard Drive
The hard disk drive (HDD) stores data magnetically on disk platters and reads it using an actuator arm and read/write head. It is a non-volatile data storage device and remains fully operational even when the computer is turned off.
HDD disks have organized magnetic surfaces that hold organizational elements such as tracks and sectors. Data is read and written by an electromagnetically charged actuator arm that scans the surface of the platters.
Modern HDD firmware is capable of scheduling reads and writes efficiently on the platter surfaces and performing error detection and correction (EDC). It also performs bad sector remapping and data collection for Self-Monitoring, Analysis and Reporting Technology (S.M.A.R.T).
Graphics Card
The graphics card gives a computer power to render on-screen video and animation smoothly. It works in conjunction with a computer’s central processing unit (CPU) to provide a high-quality visual experience for gaming, streaming and video-editing applications.
It takes binary information that comes from the CPU and converts it into pixels. These pixels are tiny squares of color that combine to form a picture on your screen. High-definition images have twice as many pixels as standard-definition ones.
Graphics cards can be either integrated or discrete. Discreet cards have their own memory and can accelerate the performance of your computer.
Sound Card
A sound card converts digital bits, the computer’s language of 1’s and 0’s, into analog signals for speakers or headphones. It also turns analog input from microphones into digital data that the computer can interpret.
Sound cards have numerous ports for connecting devices like speakers and microphones. Some have multiple 3.5 mm stereo output TRS (tip, ring, sleeve) jacks for surround sound or a MIDI port that connects a MIDI keyboard or joystick. As PC sound playback became ubiquitous and component costs decreased, it became common to incorporate basic sound card functionality into the motherboard.
Monitor
A monitor is the main output device of a computer which displays all the information processed inside it. It is also known as VDU (visual display unit).
Monitors work by processing electrical signals sent from other input devices and then illuminating pixels using screen technology. These pixels are then arranged into an image on the screen.
Monitors that support touch screens include resistive and surface wave touchscreens, which send an electrical signal when touched. They are more reliable than capacitive touch screens and are not affected by liquids or dust.