Operating Systems Overview

Operating Systems

• Definition: A set of software that manages computer hardware resources and provides common services to computer programs
• Functions:
  • Process management: creates, runs, and manages processes (programs)
  • Memory management: allocates and deallocates memory for programs
  • File system management: provides access to files and storage devices
  • Security: protects against unauthorized access and malicious code
  • Input/Output management: manages input/output operations between devices and programs
• Types:
  • Single-user, single-tasking: manages a single user and task (e.g., MS-DOS)
  • Multi-user, single-tasking: manages multiple users, but only one task per user (e.g., early Unix)
  • Multi-user, multi-tasking: manages multiple users and multiple tasks concurrently (e.g., modern Windows, macOS, Linux)
• Examples:
  • Windows
  • macOS
  • Linux
  • Chrome OS

Application Software

• Definition: A set of programs that performs specific tasks for the user
• Types:
  • Productivity software: helps users with tasks such as word processing, spreadsheet analysis, and presentation design (e.g., Microsoft Office)
  • Utility software: performs maintenance or management tasks such as disk formatting, backups, and virus scans (e.g., Norton Antivirus)
  • Malicious software: harmful programs that exploit vulnerabilities or cause damage (e.g., viruses, trojans, spyware)
  • Entertainment software: provides entertainment such as games, video players, and media editors (e.g., Adobe Premiere)
  • Educational software: teaches or trains users on specific skills or subjects (e.g., language learning apps)
• Characteristics:
  • Executable: can be run or executed by the computer
  • Platform-dependent: designed to run on specific operating systems or hardware
  • User-friendly: provides an interface for users to interact with the program
  • Customizable: can be tailored to meet specific user needs or preferences

Operating Systems

• Manage computer hardware resources and provide common services to computer programs
• Perform process management by creating, running, and managing processes (programs)
• Allocate and deallocate memory for programs through memory management
• Provide access to files and storage devices through file system management
• Protect against unauthorized access and malicious code through security features
• Manage input/output operations between devices and programs through input/output management
• Come in three types:
  • Single-user, single-tasking: manage a single user and task (e.g., MS-DOS)
  • Multi-user, single-tasking: manage multiple users, but only one task per user (e.g., early Unix)
  • Multi-user, multi-tasking: manage multiple users and multiple tasks concurrently (e.g., modern Windows, macOS, Linux)
• Examples include Windows, macOS, Linux, and Chrome OS

Application Software

• Perform specific tasks for the user
• Come in various types, including:
  • Productivity software: helps with tasks like word processing, spreadsheet analysis, and presentation design (e.g., Microsoft Office)
  • Utility software: performs maintenance or management tasks like disk formatting, backups, and virus scans (e.g., Norton Antivirus)
  • Malicious software: harmful programs that exploit vulnerabilities or cause damage (e.g., viruses, trojans, spyware)
  • Entertainment software: provides entertainment like games, video players, and media editors (e.g., Adobe Premiere)
  • Educational software: teaches or trains users on specific skills or subjects (e.g., language learning apps)
• Characterized by being:
  • Executable: can be run or executed by the computer
  • Platform-dependent: designed to run on specific operating systems or hardware
  • User-friendly: provide an interface for users to interact with the program
  • Customizable: can be tailored to meet specific user needs or preferences