Unit 1 · Session 2

Classification, Functions, and System Components

IT 231: IT and Applications (BBA)

Today's Roadmap

Classification of Computers (Micro, Mini, Mainframe, Supercomputer)
The IPOS Cycle (Input, Processing, Output, Storage)
The Five Components of an IS (Hardware, Software, Data, Procedures, People)
Business Integration & Nepal Context (Corporate & Banking Deployment)

🎯 Learning Objectives

By the end of this session, you will be able to:

✅ Classify computers across the spectrum of size, cost, and processing capacity.
✅ Trace data through each stage of the Input-Process-Output-Storage (IPOS) cycle.
✅ Identify the five vital components that transform raw hardware into a functional Information System.

Part 1: Classification of Computers

Categorizing by Physical Scale, Processing Power, and User Capacity

The Computing Power Spectrum

1. Micro

Single-user

Desktops, laptops, tablets, smartphones. Everyday productivity.

2. Mini

10s–100s users

Departmental midrange servers, campus labs, factory control.

3. Mainframe

Thousands+ users

Enterprise transactional processing, core banking, airlines.

4. Super

PFLOPS Scale

Climate modeling, quantum physics, molecular drug simulation.

Mainframes vs. Supercomputers

A common student confusion: both are massive machines, but their architectures solve completely different problems.

Feature	Mainframe Computers	Supercomputers
Primary Goal	Reliability & High Transaction Throughput	Raw Calculation Speed & Floating-Point Operations
Workload Type	Billions of simple queries (ATM, credit cards)	Complex scientific formulas & massive matrix math
Metric	MIPS (Millions of Instructions Per Second)	FLOPS (Floating-Point Operations Per Second)
Typical Users	Commercial banks, airline reservation systems	Meteorological institutes, defense, NASA

Interactive: Match the Business Need

Select the computer class needed by a commercial bank processing 8,000 ATM queries/minute across Nepal:

A) High-End Microcomputer

Custom liquid-cooled multi-core workstation

B) Supercomputer

High-performance cluster for mathematical modeling

C) Mainframe Enterprise Server

High-throughput fault-tolerant transaction engine

D) Embedded Microcontroller

Specialized low-power ROM controller

Part 2: The Functions of a Computer

The IPOS Cycle: Input · Processing · Output · Storage

The IPOS Cycle Architecture

Every computer system, from a smartwatch to an enterprise server, executes four fundamental operations:

1. Input

Captures external data into binary format.

Keyboard, Barcode Scanner, Mic

2. Process

Performs arithmetic & logical operations.

CPU (ALU + Control Unit)

3. Output

Presents human-readable results.

Monitor, Receipt Printer, Speaker

4. Storage

Retains data permanently for future retrieval.

SSD, HDD, Cloud Storage

Inside the Processing Engine (CPU)

Arithmetic Logic Unit (ALU)

The mathematical calculator of the computer:

Arithmetic: Addition, subtraction, multiplication, division.
Logical: Comparisons ($=, <, >, \le, \ge, \ne$) and Boolean operations (AND, OR, NOT).

Control Unit (CU)

The central conductor / orchestra director:

Fetches instructions sequentially from RAM.
Decodes what operation needs to be executed.
Directs data signals to the ALU, registers, and memory buses.

Storage: Volatile vs. Non-Volatile

Attribute	Primary Memory (RAM)	Secondary Storage (SSD/HDD)
Volatility	Volatile: Data lost instantly when power cuts	Non-Volatile: Retains data permanently without power
Speed	Extremely fast (Nanoseconds access)	Moderate to slow (Microseconds to milliseconds)
CPU Access	CPU communicates directly via system bus	Must first load into RAM before CPU can process
Capacity / Cost	Smaller capacity (8–64 GB), expensive per GB	Massive capacity (512 GB – 10 TB), low cost per GB

Real-World Data Flow: Supermarket Checkout

Tracking the IPOS cycle in a retail store transaction:

Input: Barcode scanner reads product EAN code $\rightarrow$ converted to binary.
Processing: CPU searches inventory table in RAM, fetches price, calculates 13% VAT and total bill.
Storage: Database writes transaction record to local SSD and updates cloud inventory count.
Output: Thermal printer generates paper bill; customer display screen shows total owed.

Part 3: The Five Components of a Computer System

Why Hardware Alone Cannot Solve Business Problems

The Five Essential Components

An Information System (IS) requires all five elements working in harmony:

1. Hardware: Physical electronic equipment (circuits, chips, drives, screens).

2. Software: Program instructions that direct hardware what to do (OS, ERP, Excel).

3. Data: Raw, unorganized facts, figures, and symbols (customer numbers, raw sales logs).

4. Procedures: Rules, operating manuals, and policies that govern how systems are run.

5. People: Users, administrators, managers, and IT personnel who interact with the system.

Why "Procedures" and "People" Matter Most

Procedures: The Missing Link

Backup schedules and emergency disaster recovery plans.
Password change policies and access authorization levels.
Without procedures, even million-dollar hardware fails to deliver security or compliance.

People: The Decisive Factor

Human error accounts for over 85% of corporate cybersecurity breaches.
Staff resistance is the #1 cause of failed enterprise ERP software rollouts.
Managerial training and digital literacy ensure system adoption.

Interactive Diagnostic: What Failed?

A hospital’s medical billing server went down, and all transaction records for the last 6 months were permanently lost because nobody had configured automated nightly backups.

Which component fundamentally failed?

A) Hardware: The storage drive was defective.

B) Software: The operating system had a bug.

C) Procedures: Lack of a backup and disaster recovery policy.

D) Data: The database schema was improperly formatted.

Managerial Summary: Session 2

Key takeaways for BBA students and future enterprise leaders:

Right-Size Hardware: Match workload to computing class (Micro for staff, Servers for departmental data, Mainframes/Cloud for high-throughput transactions).
The IPOS Cycle: Data becomes information only through methodical input, controlled CPU processing, and reliable storage.
Holistic System View: Never buy technology looking only at hardware and software — always invest equally in staff training (People) and operational SOPs (Procedures).

Thank You! 💡

Questions before we conclude this session?

Next Session: Unit 1 Session 3 · Data and Program Representation in Computers

Course Home · Read Chapter Notes

Unit 1 Session 2: Classification, Functions, and System Components | IT 231 BBA Slides