Lesson 1

• Computer is a device that can perform computations and make logical decisions, categorized based on performance and purpose into supercomputers, general-purpose computers, office computers, and workstations
• Basic Computer Organization:

  • Data enters the input unit
  • Input unit stores data in the storage unit
  • Control Unit (CU) accesses the storage unit and communicates with Arithmetic and Logic Unit (ALU), input, and output
• Input Unit includes devices like keyboard, mouse, trackball, trackpad, pointing stick, digitizer/tablet, touch panel/touch screen, image scanner, digital camera, barcode reader, OCR, sound input device, and magnetic card reader
• Output Unit includes devices like CRT display, LCD display, OLED display, laser printer, inkjet printer, dot impact printer, and thermal transfer printer
• Memory Unit is used to store programs and data required for processing in the operation of a computer, including Random Access Memory (RAM) and Read Only Memory (ROM)
• RAM is a volatile memory where data can be read and written, with two types: Dynamic Random Access Memory (DRAM) and Static Random Access Memory (SRAM)
• ROM is a non-volatile memory that retains stored content after power is turned off, with types like Mask ROM, EPROM, and EEPROM
• Machine Cycle steps:

  • Data is stored in memory from the input unit
  • Control Unit reads the data and instructs ALU to perform calculations
  • ALU performs the calculation
  • Result is stored in memory
  • Result is sent to the output unit for the user to read
• ALU performs calculations and compares items to determine equality, while CU directs operations of the computer's logic unit, memory, input, and output unit
• Number System is a set of symbols used to represent numbers, with common systems like Binary, Octal, Decimal, and Hexadecimal
• Representation of Number System:

  • The greatest symbol used is 1 less than the radix (base)
  • Progression: Once the least significant digit reaches the greatest symbol, it reverts to 0 and adds 1 to the next digit
• Radix Conversion deals with the replacement of one number system with another, like Binary to Decimal, Binary to Octal/Hexadecimal, Decimal to Base-N, etc.
• Comparison of Dynamic Random Access Memory (DRAM) and Static Random Access Memory (SRAM)

  
• Table showing binary, decimal, octal, and hexadecimal representations of numbers 0 to 15

  
• Example for Hexadecimal addition:

  • F + 1 = 10
  • 1F + 1 = 20
  • 2F + 1 = 30
• Radix Conversion:

  • Deals with the replacement of one number system with another
  • Binary → Decimal and vice versa
  • Binary → Octal/Hexadecimal and vice versa
  • Decimal → Base-N and vice versa
• Decimal fundamentals:

  • 1234 = 1 × 10^3 + 2 × 10^2 + 3 × 10^1 + 4 × 10^0
  • Expansion method: take the digit, multiply it by its place value, then sum for each digit
• Base-N to Decimal conversion:

  • Use the expansion method
  • Binary to Decimal: 1010.1112 = 1 × 2^3 + 0 × 2^2 + 1 × 2^1 + 0 × 2^0 + 1 × 2^-1 + 1 × 2^-2 + 1 × 2^-3 = 10.875
• Octal/Hexadecimal to Binary conversion:

  • For Octal, group binary numbers into 3 (23 = 8) and convert each group to decimal
  • For Hexadecimal, group binary numbers into 4 (24 = 16) and convert each group to decimal
• Search Engine:

  • Utilized when the address of a Web page a user wishes to view is not known