Computer Systems Fundamentals

Computer Systems

• A computer is an electronic device that can perform calculations, process information, and store data.

Fixed vs Programmable Computers

• Fixed computers are designed to perform a specific task and cannot be reprogrammed.
• Programmable computers can be reprogrammed to perform different tasks.

Calculators vs Computers

• Calculators are designed to perform mathematical calculations only.
• Computers are designed to perform a wide range of tasks, including calculations, processing information, and storing data.

Input and Output

• Input devices: devices that provide data or instructions to the computer, such as keyboards, mice, and scanners.
• Output devices: devices that display or produce the results of the computer's processing, such as monitors, printers, and speakers.

Memory

RAM vs ROM

• RAM (Random Access Memory): volatile memory that stores data temporarily while the computer is running.
• ROM (Read-Only Memory): non-volatile memory that stores data permanently and cannot be changed.

Secondary Storage

• Necessary because RAM is volatile and limited in capacity.
• Types of secondary storage: Hard Disk Drives (HDD), Solid-State Drives (SSD), Flash Drives, CDs, DVDs, Blu-ray Discs.
• Technologies used: magnetic, optical, solid-state.

CPU

• Components of a CPU:
  • ALU (Arithmetic Logic Unit): performs mathematical calculations and logical operations.
  • Busses: connections between components that allow data to be transferred.
  • Clock: regulates the timing of the CPU's operations.
  • Registers: small amount of memory built into the CPU.
  • Control Unit: manages the flow of data and instructions.

Operating System

• Role of the operating system:
  • Managing Memory: allocating and deallocating memory for programs.
  • Program execution: running and managing programs.
  • Managing Input and Output: controlling input/output devices.
  • Managing User Interface (GUI): providing a visual interface for users.
  • Managing Communication: managing communication between devices and programs.

Binary

• Binary is a number system that uses only two digits: 0 and 1.
• Binary can be converted to and from denary (decimal) numbers.

Binary Conversion

• Convert denary to binary: using place values (2^0, 2^1, 2^2, ...) to convert decimal numbers to binary.
• Convert binary to denary: using place values to convert binary numbers to decimal.

Binary Maths

• Binary addition: adding two or more binary numbers together.

Data Sizes

• Units of measurement for data:
  • Bit: a single binary digit.
  • Nibble: 4 bits.
  • Byte: 8 bits.
  • Kilobyte (KB): 1024 bytes.
  • Megabyte (MB): 1024 kilobytes.
  • Gigabyte (GB): 1024 megabytes.
  • Terabyte (TB): 1024 gigabytes.

This quiz covers the basics of computer systems, including the differences between fixed and programmable computers, input and output devices, RAM and ROM, secondary storage types and technologies, and CPU components.