2. What is Computer Systems?
Computer system is a complex arrangement of hardware, software, user
and data that work together to perform various task and processes.
Components of Computer Systems
Computer systems are complex entities composed of various interrelated
components that work together to perform a wide range of tasks.
These components can be broadly categorized into three main types:
Hardware,
Software, and
Users.
Each plays a crucial role in the functioning of a computer system. ta
centers.
3. 1. Hardware
Hardware refers to the physical components of a computer system. These components can
be further divided into two categories: internal components and external components.
1. INTERNAL COMPONENTS:
Internal components are housed within the computer's casing and are integral to its
operation. They include:
Central Processing Unit (CPU): Often referred to as the "brain" of the computer, the CPU
performs calculations and executes instructions necessary for computer programs.
Motherboard: This is the main circuit board that connects all the internal components,
allowing them to communicate with each other. It includes slots for the CPU, memory, and
other crucial components.
Memory: This includes both Random Access Memory (RAM) and Read-Only Memory
(ROM). RAM is the computer's short-term memory, storing data that the CPU needs quick
access to while running programs. In contrast, ROM is a type of non-volatile memory that
contains essential instructions for booting the computer and performing hardware
initialization. Unlike RAM, the data in ROM is not lost when the computer is powered off.
4. Cont..
Storage Drives: These include Hard Disk Drives (HDD) and Solid State Drives
(SSD), which store data and software permanently, even when the computer
is turned off.
Graphics Processing Unit (GPU): Responsible for rendering images and
videos, the GPU is especially important for gaming and graphic design tasks.
Power Supply Unit (PSU): This component converts electricity from the
outlet into usable power for the computer's components.
Cooling System: This is essential for maintaining optimal temperatures
within the computer. It includes fans, heat sinks, and sometimes liquid
cooling systems to dissipate heat generated by the CPU, GPU, and other
components to prevent overheating.
Ports and Connectors: These facilitate communication between the internal
components and external devices. Common ports include USB, HDMI, and
Ethernet, which allow for the connection of peripherals and network devices.
5. Cont..
2. EXTERNAL COMPONENTS
External components, or peripherals, are devices that connect to
the computer externally to expand its functionality. They include:
Monitor: The screen that displays visual output from the
computer.
Keyboard and Mouse: Input devices used for interacting with
the computer.
Printer: A device that produces hard copies of documents
and images.
External Storage Devices: Such as USB drives and external
hard drives, used for additional data storage or backup.
Speakers and Headphones: Audio output devices for sound.
6. 2. Software
Software refers to the programs and operating systems that run on a
computer system. It is the non-tangible part of the computer that tells
the hardware what to do. Software can be categorized into:
System Software: This includes the operating system (e.g.,
Windows, macOS, Linux) and utilities that manage computer
resources and provide a user interface.
Application Software: These are programs designed for end-
users to perform specific tasks, such as word processors, web
browsers, and games.
Development Software: Tools used by developers to create
other software, such as compilers and integrated development
environments (IDEs).
7. Data
These are the raw facts entered in to a computer
system that is used to make decisions, solve
problems, or might not have any meaning by itself.
However, when computed into total and average.
That data gives information such as the student’s
progress. That information can be used to make
some conclusions or develop insights about the
student.
For example, the name of a student, subjects, and
corresponding marks is a single point of data. It
8. 3. Users
Users are the people who interact with the computer
system.
They can be individuals using computers for personal
tasks, professionals using them for work, or
developers creating new software and applications.
Users play a critical role as they provide input, analyze
output, and make decisions based on the information
processed by the computer system.
9. Computer Generations
Computer generations refer to the evolution of computing technology, where each
generation represents a significant technological advancement over the previous one.
The history of computers is typically divided into five generations, each marked by a
major technological development that fundamentally changed the way computers
operate.
First Generation (1940s-1950s):
Characteristics:
Vacuum Tubes: Used for circuitry and switching.
Magnetic Drums: Used as primary memory.
Machine Language: Programming was done using machine language.
Size and Heat: Very large in size and produced a lot of heat.
Limited Operation Speed: Slow processing speeds.
Punched Cards: Used for input and output.
High Power Consumption: Required a lot of electricity.
10. Cont..
Second Generation (1950s-1960s):
Characteristics:
Transistors: Replaced vacuum tubes, making computers smaller.
Assembly Language: Programming was done using assembly
language, which is more efficient than machine language.
Magnetic Core Memory: Used for primary storage.
Batch Processing: Operations were conducted in batches.
Improved Speed and Efficiency: Faster processing speeds compared
to the first generation.
Reduced Heat: Less heat generation compared to vacuum tubes.
More Reliable: Increased reliability over the first generation.
11. Cont..
Third Generation (1960s-1970s)
Characteristics:
Integrated Circuits (ICs): Allowed for smaller and more powerful
computers.
High-Level Programming Languages: Introduction of languages
like COBOL and FORTRAN.
Multiprogramming: Capability to run multiple programs
simultaneously.
Increased Efficiency: Faster and more efficient processing.
Reduced Size: Further reduced size of computers.
Lower Cost: More affordable than previous generations.
User Interface: Development of operating systems and user
interfaces.
12. Cont..
Fourth Generation (1970s-1980s)
Characteristics:
Microprocessors: Use of microprocessors for processing, leading to the
development of personal computers.
VLSI Technology: Very Large Scale Integration technology used for creating
microprocessors.
Graphical User Interface (GUI): Development of more user-friendly
interfaces.
Networking: Introduction of computer networking and the Internet.
Portable Computers: Emergence of laptops and portable computing devices.
Enhanced Storage: Use of magnetic disks and optical discs for storage.
Reduced Cost and Size: Dramatic reduction in cost and size of computers.
13. Cont..
Fifth Generation (1980s-Present):
Characteristics:
Artificial Intelligence (AI): Incorporation of AI technologies in
computing.
Natural Language Processing: Ability to understand human language.
Parallel Processing: Use of parallel processing to increase speed.
Quantum Computing: Research and development of quantum
computers.
Advanced Robotics: Integration with robotics for more sophisticated
tasks.
Ubiquitous Computing: Pervasive computing environments.
Voice and Gesture Recognition: Advanced user interaction through
voice and gestures.
14. Future Generations
Quantum Computing: Development of quantum computers that
leverage quantum bits (qubits) for exponentially faster processing.
Neuromorphic Computing: Creation of systems that mimic human brain
functions for advanced problem-solving and pattern recognition.
Ubiquitous Computing: Integration of computing into everyday objects,
making technology seamlessly embedded in daily life.
Enhanced AI: Continued evolution of AI with greater autonomy, deeper
learning capabilities, and emotional intelligence.
Sustainability: Focus on creating energy-efficient computing solutions
that minimize environmental impact.
Advanced Interfaces: Development of more intuitive user interfaces,
including brain-computer interfaces and advanced gesture recognition.
Cost Accessibility: Further reduction in costs, ensuring that advanced
computing technology is accessible to all segments of society.
15. Classification of Computers
Computers can be classified in several ways, including by
1) Performance,
2) Portability,
3) Signal, and
4) Purpose.
Each category highlights different characteristics and functionalities of
computers, allowing users to select the most suitable device for their needs.
1) Based on Performance
(a) Supercomputers
Description: The most powerful in terms of processing capacity and speed.
Use: Used for complex simulations, weather forecasting, scientific research,
and cryptography.
Example: Summit, Fugaku.
16. Cont..
(b) Mainframe Computers
Description: Large, powerful systems used for bulk
data processing and critical applications.
Use: Employed by large organizations for transaction
processing, enterprise resource planning, and census.
Example: IBM Z series.
17. Cont..
(c) Minicomputers
Description: Mid-sized, less powerful than mainframes
but more powerful than personal computers.
Use: Used in manufacturing processes, research labs,
and small to medium-sized enterprises.
Example: VAX computers.
18. Cont..
(d) Workstation computers
Description: These are high-performance computers
designed for technical or scientific applications.
Use: They are typically used by professionals such as
engineers, architects, graphic designers, and video editors
who require powerful processing capabilities, large storage
capacity, and high-quality graphics and display capabilities.
19. Cont..
(e) Microcomputers
Description: Commonly known as personal
computers (PCs), designed for individual use.
Use: Everyday tasks such as browsing, gaming, and
document processing.
Example: Desktops, laptops, tablets.
20. Cont..
1) Based on Portability
(a) Desktop Computers
Description: Non-portable, designed to be used at a single location.
Use: Suitable for office work, gaming setups, and home use.
(b) Laptops
Description: Portable computers with integrated components, such as a
screen and keyboard.
Use: Ideal for mobile work, education, and personal use.
(c) Tablets
Description: Portable, touchscreen devices without a physical keyboard.
Use: Useful for reading, casual browsing, and entertainment.
21. Cont..
(d) Palmtops
Palmtops are small computers that literally fit in your palm.
Compared to full-size computers, palmtops are severely limited in functionality.
However, they are practical for certain functions, such as phone books and
calendars.
They are commonly known as Personal Digital Assistants (PDAs). Because of
their small size, most palmtop computers do not include disk drives.
Palmtops have small keyboards or specialized keypads tailored to specific
industries. Palmtops use pens and keyboards to input data.
22. Cont..
(e) Notebooks
Notebooks computers are small compared to laptop computers.
Besides the size and portability. The main difference between a
notebook computer and a laptop, is the display screen.
Notebook computers use various techniques, known as flat panel
technologies, to produce a lightweight and non-bulky display
screen.
The quality of notebook display screens varies considerably.
23. Cont..
3) Based on Signal
(a) Analog Computers
Description: Use continuous data and physical phenomena to perform
calculations.
Use: Employed in scientific and engineering applications for simulations.
Example: Slide rules, thermometers.
(b) Digital Computers
Description: Use discrete values (0s and 1s) for processing information.
Use: Widely used in all modern computing tasks, from simple to
complex.
Example: PCs, Smartphones.
24. Cont..
(c) Hybrid Computers
Description: Combine features of both analog and
digital computers.
Use: Used in specialized fields like robotics and process
control.
Example: Hybrid computing systems in hospitals.
25. Cont..
4) Based on Purpose
(a) General-Purpose Computers
Description: Designed to perform a wide variety of tasks.
Use: Suitable for general computing needs, from word processing to
gaming.
Example: PCs, Laptops.
(b) Special-Purpose Computers
Description: Built for a specific task or application.
Use: Used in situations where specific computations are needed, such
as ATM machines or automotive control systems.
Example: Embedded systems, calculators.
