Understanding Information Systems: Components, Characteristics, and Types

Posted on Aug 22, 2024 in Computers

Understanding Information Systems

Meaning and Elements of a System

A system is a set of interconnected things working together towards a common goal. Key elements include:

  • Components: The individual parts of the system.
  • Relationships: How the components interact and form the system’s structure.
  • Purpose: The overall objective of the system.
  • Environment: The external context surrounding the system.
  • Boundaries: The demarcation between the system and its environment.

Data Transformation into Information

Data is transformed into information through operations that add value for the user. These operations include:

  • Capture: Recording data
  • Verify: Validating data accuracy
  • Classify: Separating data into categories
  • Sort: Arranging data in sequence
  • Summarize and Calculate: Deriving logical meaning from data
  • Store: Saving data for later use
  • Recover: Retrieving stored data
  • Copy: Replicating data (e.g., on a PC)
  • Distribute: Sharing data with users

Characteristics of Information

Effective information possesses the following characteristics:

  • Available: Easily and quickly accessible
  • Precise: Free from errors
  • Relevant: Applicable to the decision-making needs
  • Timely: Current and up-to-date
  • Clear: Free from ambiguity
  • Flexible: Usable for multiple decisions and users
  • Verifiable: Consistent across multiple users and leading to the same decision

Automated Information Systems (CIS)

An information system (IS) encompasses functions, processes, and data within an organization. While an IS can exist without computers, applying computers to an IS creates a computerized information system (CIS).

Positive Effects of Computerized Systems

  • Faster information processing
  • Accurate calculations
  • Efficient handling of large data volumes
  • Increased storage capacity
  • Improved presentation of results
  • Reduced long-term costs
  • Faster access to information for decision-making
  • Enhanced information sharing among users

Negative Effects of Computerized Systems

  • High initial costs
  • Dependence on system performance
  • Rapid obsolescence of hardware and software
  • Increased need for staff training and expertise
  • Vulnerability to viruses
  • Potential staff resistance to change
  • Risk of equipment wastage

Types of Information Systems

Transactional Information Systems

These systems automate operational tasks, gather large amounts of data, and are cost-effective due to their tangible benefits.

Management Information Systems (MIS)

MIS provide information to support routine decision-making for management.

Executive Information Systems (EIS)

EIS are tailored to the strategic information needs of senior management, providing easy access to critical information for achieving organizational objectives.

Hardware Elements

Processor

  • Arithmetic-Logic Unit (ALU): Performs arithmetic and logical operations.
  • Control Unit (CU): Manages computer resources and data flow.

Main Memory

  • ROM (Read Only Memory): Non-volatile memory for storing permanent instructions.
  • RAM (Random Access Memory): Volatile memory for temporary data storage.

BIOS (Basic Input/Output System)

Firmware responsible for loading the operating system and checking hardware components.

Cache Memory

Resides within the CPU (L1 Cache) or between the CPU and RAM (L2 Cache) for faster data access.

Why is ROM called firmware?

Because it integrates both hardware and software functionalities.

Types of Buses

  • Data Bus: Transmits data between the processor, memory, and devices.
  • Address Bus: Carries memory addresses for accessing data and programs.

Software Classification

Base Software

Enables the use of computer resources.

Systems Software

Manages and controls computer resources.

Application Software

Includes software packages, expert systems, and artificial intelligence.

Programming Languages

Programming languages are sets of rules and instructions that allow humans to communicate commands to computers.

Classification

  • High-Level Languages: Resemble human language for easier programming.
  • Mid-Level Languages: Combine high-level syntax with low-level functions for greater hardware control.
  • Low-Level Languages: Closely resemble binary code for direct hardware manipulation.

Types

  • Machine Language: Uses binary code (0s and 1s).
  • Procedure-Oriented Languages: Allow writing concise statements instead of lengthy machine language instructions.
  • Object-Oriented Languages: Focus on objects and their actions, facilitating program design and understanding.

Network Operating System

Provides essential services to computers on a network, including resource sharing, security, and communication between applications.

Types of Network (Type)

  • Point-to-Point
  • Client-Server

Scope of Network

  • Local Area Network (LAN)
  • Wide Area Network (WAN)
  • Metropolitan Area Network (MAN)

Network Components and Topologies

Network Adapter

Converts data to electrical signals and controls data flow through the cable.

Network Cable

  • Twisted Pair
  • Coaxial
  • Fiber-Optic

Network Topologies

  • Linear Topology (Bus): Uses a single backbone cable.
  • Star Topology: Connects all cables to a central hub.
  • Ring Topology: Connects each host to the next in a circular pattern.
  • Mesh Topology: Provides maximum redundancy and fault tolerance.
  • Hybrid Topology: Combines elements of different topologies (e.g., star-bus, star-ring).
  • Extended Star Topology: Connects multiple star networks through hubs or switches.
  • Hierarchical Star Topology: Similar to extended star, but with a central computer controlling traffic.

Network Expansion and Connectivity

Network Devices

  • Repeater
  • Hub
  • Bridge
  • Switch
  • Router
  • Gateway