Unit 1-2 Basic computer and fundamentals

History of Computers

The history of computers dates back to the 19th century, when early mechanical calculators were first developed. These machines were designed to perform simple mathematical calculations, such as addition, subtraction, multiplication, and division.

The first electronic computers were developed in the mid-20th century, and were primarily used for scientific and military applications. The first electronic computer was the Atanasoff-Berry Computer (ABC), which was developed in 1937-1942. However, it was not fully functional and was not widely used.

The first fully functional electronic computer was the Electronic Numerical Integrator and Computer (ENIAC), which was developed in 1945. ENIAC was used primarily for military calculations, such as the trajectory of artillery shells.

In the 1950s and 1960s, computers began to be used for business and commercial applications, such as payroll processing and inventory management. These computers were typically large mainframe computers, which were expensive and required specialized facilities to operate.

The development of the microprocessor in the 1970s revolutionized the computer industry, making it possible to build small, affordable computers that could be used by individuals and small businesses. The first microcomputers were introduced in the mid-1970s, including the Apple II and the Commodore PET.

The 1980s saw the widespread adoption of personal computers, with the introduction of the IBM PC and the rise of Microsoft Windows. In the 1990s, the Internet became widely available, and computers began to be used for communication and information sharing on a global scale.

Since the turn of the 21st century, the development of mobile devices and the Internet of Things (IoT) has further expanded the role of computers in everyday life. Today, computers are an essential part of modern society, used for everything from personal communication and entertainment to scientific research and space exploration.

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Generations of Computers

There are five generations of computers, each of which represents a significant advancement in computer technology:

First Generation Computers (1940s-1950s): The first generation of computers used vacuum tubes for processing, and were large, expensive, and unreliable. They were primarily used for scientific and military applications.

Second Generation Computers (1950s-1960s): The second generation of computers used transistors instead of vacuum tubes, making them smaller, faster, and more reliable. They were used for business and scientific applications.

Third Generation Computers (1960s-1970s): The third generation of computers used integrated circuits, which allowed for even smaller and more powerful computers. They were used for a wide range of applications, including scientific research, business, and government.

Fourth Generation Computers (1970s-1980s): The fourth generation of computers used microprocessors, which combined multiple integrated circuits into a single chip. This led to the development of personal computers, which were smaller, more affordable, and easier to use.

Fifth Generation Computers (1980s-Present): The fifth generation of computers is still evolving, and is focused on developing advanced technologies such as artificial intelligence, natural language processing, and quantum computing. These technologies are designed to enable computers to perform more complex tasks, such as pattern recognition and decision-making, that were previously thought to require human intelligence.

Each generation of computers has led to significant advances in computer technology, making computers more powerful, faster, and easier to use. Today, computers are an essential part of modern society, used for everything from personal communication and entertainment to scientific research and space exploration.

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Computer Input Devices

There are many different types of input devices for computers, including:

1.Keyboard: A keyboard is the most common input device for a computer, and
 it allows you to type in letters, numbers, and symbols.

2.Mouse: A mouse is used to move the cursor around the screen and to select
 and activate items.
3.Touchpad: A touchpad is a small, flat pad that allows you to move the cursor
 around the screen by sliding your finger across its surface.

4.Trackball: A trackball is a ball-shaped device that allows you to move the
 cursor by rolling the ball with your fingers.

5.Joystick: A joystick is a device used for controlling video games, flight simulators,
 and other applications that require precise directional control.

6.Scanner: A scanner is an input device that can be used to digitize images, documents,
 and other physical objects.

7.Microphone: A microphone is used to record audio input, such as voice commands,
 for various applications like voice assistants or recording software.

8.Webcam: A webcam is used to capture video input, such as for video conferencing or
 recording videos.

9.Touchscreen: A touchscreen is a display that allows you to interact with the computer
 by touching the screen directly.

10.Graphics Tablet: Graphics tablet is an input device that allows you to draw or
 write directly on a digital surface using a stylus, it's commonly used by artists and designers.

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Computer Output Devices

Output devices are the computer peripherals that display or transmit the results
 of processing data or information from the computer to the user. Here are some common output devices:
1.	Monitor/Display: Displays visual output, such as images, videos, and text.
2.	Printer: Prints hard copy output, such as text and images, onto paper.
3.	Speakers: Output audio output, such as music, speech, and sound effects.
4.	Projector: Displays visual output on a larger screen or wall.
5.	Headphones: Output audio output directly to the user's ears.
6.	Plotter: A device that draws graphics or designs on paper or other materials.
7.	Braille display: Displays text output in Braille for visually impaired users.
8.	Touchscreen: A display that allows users to interact with the computer by 
touching the screen.
9.	Joystick: A peripheral device that outputs control signals for video games
 or other applications.
10.	Microphone: Input/output device that converts sound waves into electrical 
signals for recording or transmitting audio data.

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Different Types Memories

There are different types of computer memory that serve different purposes in a 
computer system. Here are some common types of memory:

1.	Random Access Memory (RAM): RAM is a type of volatile memory that stores data 
and program instructions that are currently being used by the computer. 
RAM is temporary, and its contents are lost when the computer is shut down.



2.	Read-Only Memory (ROM): ROM is a type of non-volatile memory that stores 
data and instructions that are essential for the computer to operate. ROM cannot be modified by the
 user and retains its contents even when the computer is turned off.



3.	Cache Memory: Cache memory is a type of high-speed memory that is used to 
store frequently accessed data and instructions. It is located between the CPU and the main memory
 and helps improve the performance of the computer.



4.	Flash Memory: Flash memory is a type of non-volatile memory that is used to 
store data and program instructions. It is commonly used in portable devices, such as USB drives,
 memory cards, and solid-state drives.



5.	Hard Disk Drive (HDD): HDD is a type of non-volatile storage device that stores
 data on spinning magnetic disks. It provides high-capacity storage at a low cost.



6.	Solid State Drive (SSD): SSD is a type of non-volatile storage device that uses 
flash memory to store data. It is faster and more reliable than HDD but is more expensive.



7.	Optical Storage: Optical storage devices, such as CD, DVD, and Blu-ray discs,
 use laser technology to read and write data. They are commonly used for storing and sharing 
large files, such as music and video.



8.	Magnetic Tape: Magnetic tape is a type of storage media that uses magnetic particles
 to store data. It is commonly used for backup and archival purposes.

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