Looking for comprehensive PGDCA (Post Graduate Diploma in Computer Applications) notes on Components of Computer for the 2026–27 academic session? Access complete theory explanations, functional block diagrams, short notes, long analytical answers, objective MCQs, and exam-oriented solutions covering fundamental computer architecture, System Unit, Motherboard, Hardware vs. Software, CPU (ALU, CU, Registers), Memory units, Input/Output peripherals, Expansion slots, Power Supply (SMPS), and Data Bus architecture tailored for university diploma exams.
Components of a Computer
Computer architecture follows the classic Von Neumann Architecture, comprising four fundamental functional units:
+———————————–+
| CENTRAL PROCESSING UNIT |
| |
+————–+ | +—————————–+ | +—————+
| INPUT UNIT |—> | CONTROL UNIT (CU) | |—> OUTPUT UNIT |
+————–+ | +—————————–+ | +—————+
| | ARITHMETIC LOGIC UNIT(ALU) | |
| +—————————–+ |
+—————–+—————–+
|
v
+——————-+
| MEMORY UNIT |
| (Primary/Secondary)|
+——————-+
- Input Unit: Converts user data and commands into machine-readable binary form.
- Central Processing Unit (CPU): The primary brain of the system that controls and processes all instructions.
- Memory Unit: Stores programs, active data, and finalized output.
- Output Unit: Translates processed binary results into human-readable text, graphics, or audio.
PGDCA Components of Computer Notes
Q1. List the four main functional units of a computer. [2 Marks]
Answer:
- Input Unit
- Central Processing Unit (CPU)
- Memory / Storage Unit
- Output Unit
PGDCA Block Diagram of Computer Important Questions 2026-27
Q2. What is the role of the Input Unit? [2 Marks]
Answer: The Input Unit receives raw data and human instructions from peripheral devices, converts them into machine-readable binary code (0s and 1s), and transmits them to primary memory for processing.
Q3. Describe the function of the System Bus. [3 Marks]
Answer: The System Bus is a group of physical wire traces that transfers data, memory addresses, and control signals between the CPU, primary memory, and I/O devices. It consists of:
- Data Bus: Carries actual data values.
- Address Bus: Carries physical memory addresses.
- Control Bus: Carries command signals from the Control Unit.
Components of Computer PGDCA Syllabus Question Answer
Q4. What is the primary function of the Output Unit? [2 Marks]
Answer: The Output Unit accepts processed binary data from the computer’s memory and converts it into human-understandable visual, printed, or audio forms.
PGDCA Hardware and Software Components Solutions
Q5. Explain the interaction between the CPU and Memory Unit. [3 Marks]
Answer:
- The CPU fetches program instructions and data from the Primary Memory (RAM) into internal registers via the bus system.
- The CPU executes the instructions inside the ALU or Control Unit.
- The CPU stores the intermediate or final execution results back into Primary Memory.
🖥️ PGDCA Exam Preparation Notice: This page provides curated PGDCA (Post Graduate Diploma in Computer Applications) Components of Computer Study Material & Solutions updated for the 2026–27 academic session. This complete guide features functional computer block diagrams, motherboard component breakdowns, System Bus interactions (Data, Address, Control Bus), hardware-software synergy charts, and high-yield exam questions designed to help you secure top marks in your semester examinations.
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