CS2 1.1-1.3

  • An operating system is the primary software on a computer that manages all the hardware, such as the keyboard, monitor, and sound card, and is essential for the computer to work properly.

  • The operating system allows users to communicate with a machine or computer, taking care of basic uses such as taking in user input, running applications, and saving files.

  • Operating systems manage and keep track of all files and folders, and allow users to install and run other software or applications.

  • Most operating systems allow users to set up user accounts with passwords and specific permissions for each account, helping with system security.

  • Operating systems can schedule updates, perform tasks, and processes, such as forcing a program to close if it stops responding.

  • There are different types of operating systems, including workstation OS, mobile operating systems, server operating systems, embedded operating systems, firmware, and hypervisors.

  • Workstation OS is commonly used on desktop or laptop computers and can perform many tasks without an internet connection.

  • The three most widely used operating systems are Microsoft Windows, Apple Macintosh (also known as Macs), and Linux.

  • Mobile operating systems, such as Android and iOS, are used on phones, tablets, and other mobile devices.

  • Chrome OS is used on Chromebooks, which can be classified as either a workstation or mobile operating system.

  • Server operating systems are used on specialized computers that take in requests and send back responses, such as mail servers or web servers.

  • Embedded operating systems perform specific tasks and are used in machines such as ATMs or GPS systems.

  • Firmware is a type of operating system that takes care of lower-level tasks and is permanently etched into hardware devices such as keyboards or video cards.

  • Hypervisors allow one host computer to support multiple guest devices by virtually sharing resources like memory and processing.

  • The top three operating systems are Microsoft Windows, Apple Macintosh, and Linux, with Microsoft Windows being the most popular due to its large industry support and wide range of applications.

  • Microsoft Windows has a large user base, making it a target for security exploitation, but many operating systems now use a graphical user interface (GUI) to provide a simpler way to use the system.

  • Apple Macintosh computers are also extremely popular, known for being easy to use and having good security features, but are typically more expensive than Windows systems.

  • Linux is a free and open-source operating system that is very different from Windows and Macs, with many different versions available due to its open-source nature, but it has limited support and compatibility.

  • All operating systems use different types of file systems, which are methods for storing files, and each operating system has its own preferred file system.

  • The top four file systems used today are FAT32, NTFS, ext4, and HFS, each with its own unique features and memory capacities.

  • FAT32 is compatible with all three major operating systems and is commonly used for USB drives and memory cards, with a memory limit of 16 terabytes.

  • NTFS is a Windows file system that comes with additional features and more memory than FAT32, with a memory capacity of one exabyte.

  • ext4 is used on Linux systems and also has a memory capacity of one exabyte, while HFS is a Mac file system with the most memory available, capped at eight exabytes.

  • File systems can perform various functions, including compressing and encrypting files, setting user permissions, and keeping track of changes, which are important for security and data management.

  • Each operating system has its own way of storing and viewing files, and a file manager is a program that allows users to view, open, move, and rename files, with different programs working slightly differently.

  • File extensions are the text that comes after the period in the name of the file, and the operating system uses this to determine which program or application to use to open the file.

  • Some file extensions, such as PDF and JPG, can be used on all computers as long as the user has an app to open them, while others, such as DOC and DOCX, are more commonly used on specific systems but can still be opened on other systems with the correct application.

  • Certain file extensions, such as PAGES, are exclusive to specific systems, and while they can be opened on other systems by changing the file extension, they cannot be strictly opened with their original extension.

  • Linux uses the way the file is coded to decide which program to use to open the file, rather than looking at the extension.

  • Operating systems have their own procedures for processing information, and some systems may need more memory to open a file or run a program, making it essential to know the computer's processor.

  • A processor, also known as a CPU or central processing unit, executes the instructions passed to it by the operating system, and a 64-bit processor is stronger than a 32-bit processor, capable of storing more values and information and handling more data at one time.

  • A 64-bit processor has over 4 billion times the physical memory of a 32-bit processor, and while a 32-bit operating system can usually run on a 64-bit processor, the reverse is not true.