Micro Computers and Input Devices

Micro Computers

• Term “micro” signifies small size, suitable for desk use, in contrast to large computers occupying entire rooms.
• Common uses include internet browsing, gaming, document writing, and video watching.
• Examples: laptops, desktops, tablets, smartphones.

Standard Input Devices

• Keyboard: Most frequently utilized input device; functions similarly to a typewriter.
• Contains keys for letters, numbers, and special characters.

Types of Keyboards

• General Purpose Keyboard: Standard for personal computers; includes approximately 101 keys common across applications.
• Special Purpose Keyboard: Designed for specific applications requiring faster data entry.

Functions of Input Devices

• Input devices accept data from the external environment and convert it into computer-readable format.
• The processed data is sent to the Central Processing Unit (CPU) for further operations.

Keyboard Layout

• Alphanumeric Keypad: Central part of the keyboard containing letters, numbers, and special signs.
• Numeric Keypad: Rightmost section with digits (0-9) and mathematical symbols, primarily used for quick data entry.
• Arrow Keys: Facilitate cursor movement; also called cursor-control keys.

Function Keys

• First row consists of 12 function keys (F1 to F12) to generate shortcuts in software.

Special Keys

• Print Screen: Captures the current screen display.
• Insert: Allows text insertion between characters.
• Esc: Cancels commands.
• Caps Lock: Types capital letters.
• Tab: Moves the cursor to the next predefined position.
• Space: Creates a blank space between words.
• Delete: Deletes characters at the cursor position.

Pointing Devices

• Computer Mouse: Hand-held device sensing 2D motion to navigate the cursor on screen.
• Trackball: Stationary device with a rotating ball controlled by fingers.
• Joystick: Contains a stick for cursor movement; useful in gaming.
• Touch Screen: Interactive display allowing users to select options by touch.

Graphics Tablet

• Input device enabling hand-drawn graphics creation using a stylus, similar to pencil drawing.

Computer Generations

• First Generation (1946): ENIAC, the first large-scale electronic digital computer.
• Second Generation (1947): Introduction of transistors replacing vacuum tubes for better efficiency.
• Third Generation (1959): Development of integrated circuits, paving the way for microchips.
• Fourth Generation (1971): Introduction of microprocessors, with Intel 4004 hosting 2300 transistors.

Classification of Computers

• Supercomputers: Highly powerful, used for complex calculations and simulations in research fields.
• Mainframe Computers: Large, powerful systems used by organizations to manage massive data volumes.
• Minicomputers: Smaller, less powerful alternatives to mainframes, often used in companies.
• Microcomputers: Common personal computers typically used by individuals.