1

Computer

• A computer is an advanced electronic device
• It takes raw data as input from a user
• It processes the data under the control of a set of instructions (a program)
• It produces output, and saves it for future use
• It is essential in today's information-rich world

Computer Functionalities

• Takes data as input
• Stores data/instructions in memory for later use
• Processes data and instructions to create useful information
• Generates output
• Controls all the above steps

Computer Definition

• A computer is an electronic data processing device
• It accepts and stores input data
• It processes the input data
• It produces output in a required format

Computer Advantages

• High speed: Performs calculations very quickly compared to humans
• Accuracy: Calculates with 100% accuracy if correct input is given
• Storage Capacity: Stores large amounts of data (images, videos, text, audio)
• Diligence: Never gets bored or tired; works continuously without errors
• Versatility: Performs various tasks, from complex scientific calculations to simple games
• Reliability: Modern electronics have long lifespans, and maintenance is easy

Computer Disadvantages

• No Intelligence: Cannot perform tasks independently; needs instructions for every task
• Dependence: Operates as per user instructions; cannot make decisions itself
• Environmental Needs: Requires a suitable, dust-free environment
• No Emotions: Lacks emotions, feelings, taste, experience, and judgment like humans

Applications of Computers

• Business: Payroll calculations, budgeting, financial forecasting, sales analysis, managing employee records, and maintaining stock
• Banking: Online accounting, balances, deposits, overdrafts, interest, charges, share-related activities, and handling trustee records.
• Insurance: Keeping records updated, maintaining client databases with information about policies, policy start dates, installments, maturity dates, interest due and bonus details.
• Education: Computer-Based Education (CBE); controlling, delivering, and evaluating learning; improving student numbers
• Marketing: Advertising, writing and revising ads and creating graphics to promote goods and services; enabling home shopping

Computer Generations

• Five generations of computers have been developed, each with different technologies
• First Generation (1946-1959): Vacuum tube based computers.
• Second Generation (1959-1965) : Transistor-based computers.
• Third Generation (1965-1971): Integrated Circuit-based computers.
• Fourth Generation (1971-1980): VLSI microprocessor based computers.
• Fifth Generation (1980-onwards): ULSI microprocessor based computers.

Computer Types

• Different computers have various designs and features based on requirements(capacity, speed)
• Mainframe computers: High capacity machines for simultaneous use by many users.
• Supercomputers: Fastest computers capable of handling trillions of calculations per second
• Workstations: Expensive, high-end computers for complex tasks.
• Personal Computers (PCs): Low-capacity machines for single users
• Laptops: Portable personal computers.
• Tablets and Smartphones: Pocket-friendly, modern devices

Computer Organization

• Input Unit: Enters data into the computer
• Memory Unit: Stores data and instructions for processing
• Processing Unit: Processes data using arithmetic and logic operations
• Output Unit: Displays processed information to the user

Computer input devices

• Keyboard, Mouse, Joystick, Light Pen, Trackball, Scanner, Microphone, Magnetic Ink Card Reader (MICR), Optical Character Recognition (OCR), Bar Code Reader, Optical Mark Reader (OMR), Digitizer

Computer Memory

• Main Memory (Primary): Stores data and instructions currently used

• Secondary Memory (Secondary): Stores data and instructions permanently.

• Cache Memory: Stores frequently used data and instructions for faster access

• Primary memory: Volatile: Contents lost if power cut. Examples include RAM: Random Access Memory

• Secondary memory: Non-volatile: Contents remain even if power cut. Examples include ROM: Read Only Memory, Hard disk.

Computer Mother Board

• A motherboard connects all computer components. It is the backbone
• It holds the CPU, memory, hard drives, video/sound card, and expansion cards.
• Different types of supports for different components like video cards and hard disks.
• Compatible components are needed to work together effectively.
• Different motherboard manufacturers include Intel, Asus, Biostar, Gigabyte, and MSI.