Basics Parts of Computer and their functions (Explained with Example)

A computer stands for “Commonly Operated Machine Particularly Used for Technological and Educational Research”. It is an electronic device designed to process data and perform tasks based on instructions provided by software. It functions through a combination of physical components, known as hardware, and sets of instructions, known as software. In simple terms, a computer takes input, processes it, stores it, and produces output, a cycle known as the Input–Process–Output (IPO) model. Computers are used in almost every field today, from education, healthcare, and business to entertainment and research. However, behind every powerful operation, there is a set of basic parts that make it work efficiently. In this article, we explore the basic parts of a computer and their functions.

Parts of Computer system and its functions

A computer system consists of hardware (the physical parts) and software (the programs or instructions). Key hardware components include the CPU (processing), RAM (short-term memory), storage (long-term memory), motherboard (connecting all parts), and power supply (powering components). Input devices like a keyboard and mouse, and output devices like a monitor and speakers, are also essential parts of the system.

Central Processing Unit (CPU) – The Brain of the Computer

The CPU, or Central Processing Unit, is often called the “brain of the computer.” It executes instructions from programs and performs all logical, arithmetic, and control operations.

It interprets and executes instructions from both hardware and software.

Main functions of the CPU include:

• Processing Data: Handles calculations and logical operations.
• Controlling Operations: Directs the functioning of other components like memory and input/output devices.
• Executing Instructions: Follows software commands step by step to perform tasks.

Main Components of CPU:

• ALU (Arithmetic Logic Unit): Handles mathematical and logical operations.
• CU (Control Unit): Directs the flow of data and instructions within the system.
• Registers: Store small bits of temporary data for fast access.

When you open a program, the CPU retrieves data from memory, processes it, and sends results to output devices. Without the CPU, no program or operation could be executed it’s the heart of all processing.

Modern CPUs are manufactured by companies like Intel and AMD and are installed on the motherboard via a dedicated socket.

Random Access Memory (RAM) – The Working Memory

Random Access Memory (RAM) is a type of volatile memory that temporarily stores data and instructions that the CPU needs while the computer is running. When you shut down your computer, all data in RAM is lost.

Types of RAM:

• DRAM (Dynamic RAM): Common in personal computers.
• SRAM (Static RAM): Faster and used in cache memory.

Functions of RAM:

• Stores temporary data for quick access by the CPU.
• It helps the CPU process multiple tasks efficiently.
• Improves system speed and performance.

The more RAM your system has, the more programs it can run simultaneously without lag.

In contrast, Read-Only Memory (ROM) is non-volatile and stores permanent instructions like the BIOS. The CMOS battery on the motherboard powers settings storage, ensuring system time and configuration are retained.

Hard Drive or SSD (Storage Device) – The Data Storage Center

Every computer requires a permanent storage location for data. This is where storage devices like HDDs (Hard Disk Drives) or SSDs (Solid State Drives) come in. Unlike RAM, storage devices store data permanently even after the computer is turned off. They hold the operating system, applications, files, and media.

Hard Disk Drives (HDDs) use spinning magnetic disks, offer large capacity at lower cost. Solid-State Drives (SSDs) use flash memory, deliver faster boot times and data access.

Other storage forms include optical drives (CD/DVD/Blu-ray) and USB flash drives. Cloud storage also allows remote data access.

Functions:

• Stores the operating system, software, documents, and media files.
• Retains data even when the computer is powered off.
• SSDs are faster, more reliable, and energy-efficient compared to HDDs.

Tip: Upgrading from an HDD to an SSD can dramatically boost system performance and boot time.

Motherboard – The Backbone of the Computer

The motherboard is the main circuit board that connects all components of the computer. It provides communication between the CPU, memory, storage, and input/output devices. It also includes BIOS/UEFI firmware, which initializes hardware during boot-up. Key manufacturers include ASUS, Gigabyte, and MSI.

Key Parts on the Motherboard:

• CPU socket
• RAM slots
• Storage connectors (SATA/M.2)
• GPU/PCIe slots
• USB and power connectors

How it Functions:

• It acts as a central hub, ensur smooth communication between all parts (CPU, RAM, GPU, storage, etc.).
• It enables communication between the CPU, memory (RAM), and other devices like graphics cards and storage (SSDs, hard drives).The motherboard receives power from the power supply and distributes it to all connected components.

  It contains expansion slots, such as PCIe slots, which allow users to add components like dedicated graphics cards or sound cards.

• It includes various connectors for storage devices (SATA, M.2) and power.
• The back of the motherboard features ports for external devices, including USB, Ethernet, and audio jacks, and may include video outputs like HDMI or DisplayPort.
• It houses the BIOS or UEFI firmware, which is essential for the computer to boot up and start the operating system.

Without the motherboard, no component can communicate or function properly.

Power Supply Unit (PSU) – The Energy Provider

The power supply (SMPS – Switched-Mode Power Supply) converts electric current (AC power) from the wall socket into the DC voltage that the computer’s internal components can use. It provides stable power to the motherboard, CPU, drives, and other peripherals.

A single SMPS provides the various DC voltages needed, such as +3.3V, +5V, and +12V, through different connectors.

How it works

• The SMPS takes the AC power and first converts it to pulsating DC using a rectifier and filter.
• It then uses a high-frequency switch to chop the pulsating DC into a high-frequency signal.
• A transformer then steps down this high-frequency signal to the required lower voltage.
• Finally, the signal is rectified and filtered again to produce a smooth, stable DC output.
• Control circuitry constantly monitors the output voltage and adjusts the switching to maintain a constant output level

Monitor (Display Screen) – The Output Device

The monitor displays visual information such as text, images, videos, and user interfaces. Modern monitors use LED or LCD technology for better color accuracy and energy efficiency.

• A monitor receives video signals from the computer’s graphics card and translates them into the images, text, and videos you see on the screen.
• A monitor typically includes a display panel, supporting circuitry, a power unit, and ports for connecting to a computer.
• Common monitor technologies include LED (Light-Emitting Diode) and LCD (Liquid Crystal Display), which are energy-efficient and widely used today.  OLED (Organic Light-Emitting Diode) monitors are newer and offer vibrant colors and deep blacks.
• Supports multiple resolutions and refresh rates depending on use (e.g., gaming, design, or office work).

Graphics Processing Unit (GPU) – For Image and Video Rendering

A graphics card includes a GPU (Graphics Processing Unit), is responsible for rendering images, videos, and animations. It works alongside the CPU but specializes in handling visual and graphical data.

Types of GPU:

GPUs can be integrated into the CPU or installed as a separate card on the motherboard.

• Integrated GPU: Built into the CPU (e.g., Intel UHD Graphics).
• Dedicated GPU: A separate graphics card (e.g., NVIDIA GeForce, AMD Radeon) used for high-performance graphics.

Functions:

• It’s responsible for processing and outputting visual data to a computer monitor.
• The GPU is the chip that performs the heavy lifting for graphics and is designed for parallel processing.
• Enhances gaming, video editing, and 3D rendering performance.
• Offloads graphic-intensive tasks from the CPU for faster overall performance.

While originally designed for gaming and graphic design, modern GPUs are also used for other demanding, parallel processing tasks like artificial intelligence (AI), machine learning (ML), and high-performance computing (HPC).

A powerful GPU improves gaming performance, video playback, and overall graphics quality crucial for content creators and gamers.

Graphics card vs. GPU: 

A graphics card is the entire component that houses the GPU, along with its own dedicated memory and cooling system, while the GPU is the specific processor chip on that card.

Input Devices

Input devices are hardware components that allow users to send data, commands, and signals to a computer system for processing. These devices translate physical actions or environmental data into electronic signals that the computer can interpret to perform tasks.

Examples and Usage:

• Keyboard: Used to type text, numbers, and commands.
• Mouse: Helps move the cursor and select items on the screen.
• Scanner: Converts printed documents or images into digital form.
• Microphone: Used to input sound or voice data.

Without input devices, the computer cannot receive any instructions or data from the user.

Output Devices

Output devices are hardware components that convert processed data from a computer into a form humans can understand, such as visual, audio, or physical copies

Examples and Usage:

• Monitor: Displays text, images, and videos.
• Printer: Produces a physical copy of documents.
• Speakers: Output sound, music, and alerts.

These devices allow users to see, hear, or print the computer’s output.

Cooling System (Fans or Liquid Coolers) – Keeps Temperature Under Control

Computers generate heat during operation, especially while running heavy applications. Cooling systems help maintain optimal temperatures.

• Prevents overheating of the CPU and GPU.
• Ensures consistent performance and prolongs component lifespan.
• Can include air coolers (fans) or liquid cooling systems in high-performance PCs.

Network Interface Card (NIC) – For Internet Connectivity

The NIC allows your computer to connect to local networks or the internet, either via Ethernet cable or Wi-Fi.

• Facilitates data transmission between your computer and the network.
• Enables online communication and file sharing.
• Can be integrated into the motherboard or installed as an expansion card.

How Computer Parts Work Together

Computer components work together through a central hub called the motherboard, which connects all parts like the CPU, RAM, and storage.

• Input devices (keyboard/mouse) send data to the CPU.
• The CPU processes the data using instructions stored in RAM.
• Processed information is stored temporarily or permanently in storage devices.
• The GPU and monitor handle display output.
• The motherboard ensures communication between all these parts.

Frequently Asked Questions (FAQs)

What are the 5 basic parts of a computer?
The five basic parts are the CPU, motherboard, memory (RAM), storage device (HDD/SSD), and power supply unit (PSU). These components are essential for the computer to function.

What is the main function of the CPU?
The CPU processes data, executes instructions, and manages operations across all hardware components. It’s often called the brain of the computer.

What is the difference between RAM and storage?
RAM temporarily stores data for quick access while the system is running, whereas storage devices (HDD or SSD) permanently store data even after the computer is turned off.

Can a computer work without a GPU?
Yes, most CPUs have integrated graphics that allow a computer to display basic visuals. However, a dedicated GPU is needed for gaming, 3D design, and video editing.

Why is the motherboard important in a computer?
The motherboard connects all hardware components and enables communication between them. Without it, the CPU, RAM, and other parts can’t work together.