hardware

• Different names for software:

  • Application (app)
  • Program
  • Executable (file extension .exe)
• Classification of software:

  • System software: allows the computer to run, includes operating system (OS), utility programs, library routines, and translators
  • Application software: extras that can be downloaded, allows users to perform tasks such as image manipulation, word processing, etc
• Operating system (OS) is the most important software that runs on a computer, manages the computer's memory, processes, software, and hardware
• Operating system functions:

  • Manages the processor's functions such as I/O devices, memory, applications, processors, and security
  • Most operating systems use a graphical user interface (GUI) for user interaction
  • Some computers have multiple processor cores (e.g., dual-core, quad-core)
• Control unit:

  • Coordinates and controls all operations in the computer
  • Monitors hardware, controls input/output data, regulates processor timing using a clock
• Clock:

  • Switches between 0 and 1 continuously to regulate processor timing
  • Measured in Hertz (Hz), frequency of clock cycles per second
• Arithmetic Logic Unit (ALU) performs:

  • Arithmetic operations (addition, subtraction, multiplication, division)
  • Logical operations (AND, OR, NOT)
  • Shift operations
• Fetch-Decode-Execute cycle:

  • CPU operations involve fetching, decoding, and executing instructions
• Three buses:

  • Address bus: sends the address of the next instruction to be fetched
  • Data bus: sends data between processor, memory, and storage
  • Control bus: carries signals to show bus usage status
• Main types of storage:

  • Magnetic (e.g., hard drives)
  • Optical (uses lasers)
  • Solid-state (e.g., SD cards)
• Device driver:

  • Software program that tells the CPU how to communicate with hardware
• Hard disk drive:

  • Virtual memory slows down computer
  • Advantages of virtual memory: handles more addresses, enables more applications, saves users from adding memory modules
  • Disadvantages: applications may run slower, takes time to switch between applications, reduces system stability
• Cloud computing advantages:

  • Usability and accessibility
  • Security
  • Cost-efficient
  • Convenient sharing of files
  • Automation
  • Multiple users
  • Synchronization
  • Convenience
• RAM (Random Access Memory) stores data temporarily while it’s being used by your computer.
• The motherboard connects to the CPU, RAM, hard drive, optical drives, keyboard, mouse, monitor, speakers, and network card.
• • Utility software: 


  supports computer system operation safely and efficiently
• • Maintenance:

  keeps devices running by updating software
• Encryption software:


  disguises file contents for authorized users only.
• • Embedded systems: 


  small computers that control larger systems or devices with limited tasks