Introduction to Computers Quiz

Study Notes

A computer is a programmable electronic device that accepts data, performs arithmetic and logical operations, and produces output.
Input refers to raw data given to the computer, while output is the processed information received.

The term "Computer" originated in 1640, describing "one who calculates," from the Latin word 'computare' meaning 'to calculate.'
Early computers were large, filling entire rooms.
Charles Babbage invented the 'difference engine' in 1833 and introduced the first general-purpose mechanical computer, the 'Analytical Engine,' in 1837.

Input Unit:
- Receives data through devices such as mouse, keyboard, and scanner, acting as a mediator between users and the computer.
- Converts data into machine-readable form and transmits it to the main memory.
Central Processing Unit (CPU):
- Known as the brain of the computer; it oversees all tasks and operations.
- Consists of two main units: Arithmetic Logic Unit (ALU) and Control Unit (CU).
Arithmetic Logic Unit (ALU):
- Performs basic arithmetic operations (addition, subtraction, multiplication, division) and logical operations (AND, OR, etc.).
- Responsible for data merging, sorting, and selection.
Control Unit (CU):
- Acts as the coordinator of all computer activities by converting instructions into control signals for task prioritization and scheduling.
Memory Unit:
- Stores both processed and unprocessed data; works in sync with the CPU for efficient data access.
- Divided into two types: Primary Memory (temporary) and Secondary Memory (permanent).

Primary Memory:
- Temporary storage that holds recently processed data, susceptible to erasure when power is off.
- Example: RAM (Random Access Memory) is directly accessible by the CPU for reading and writing.
Secondary Memory:
- Permanent storage for data that remains intact during power failures.
- Example: Hard disk acts as auxiliary memory, ensuring data persistence.