Operating Systems Presented by Abigail Atiwag Operating systems OS are software systems that manage computer hardware software resources and provide services for computer programs and users Here are key topics related to operating systems Types of Operating Systems Desktop Operating Systems OS for personal computers and workstations including Windows macOS formerly OS X and Linux distributions e g Ubuntu Fedora CentOS Server Operating Systems OS designed for server environments such as Windows Server Linux server distributions e g CentOS Ubuntu Server Red Hat Enterprise Linux and UNIX based systems e g FreeBSD Solaris Types of Operating Systems Mobile Operating Systems OS for mobile devices smartphones and tablets including Android iOS Apple and Windows Mobile discontinued Embedded Operating Systems OS for embedded systems and devices e g IoT devices automotive systems such as Embedded Linux FreeRTOS and Windows Embedded Operating System Functions Process Management Managing processes scheduling CPU time allocating resources and ensuring efficient multitasking and multiprocessing Memory Management Allocating and managing system memory RAM virtual memory memory paging and memory protection Operating System Functions File System Management Organizing storing and accessing files and directories on storage devices e g hard drives SSDs flash drives using file systems e g NTFS FAT32 ext4 HFS Device Management Managing input output I O devices e g keyboards mice printers network interfaces device drivers and communication with hardware components Operating System Functions User Interface Providing graphical user interfaces GUIs command line interfaces CLIs and system utilities for user interaction system configuration and administration Security and Access Control Enforcing user authentication access permissions encryption firewall configurations and system security policies Operating System Functions Networking Supporting network protocols communication and network configurations e g TCP IP stack network drivers network services Operating System Components Kernel Core component of the OS that manages system resources processes memory and hardware interactions Shell Command interpreter or user interface that allows users to interact with the OS execute commands and run programs e g Bash shell PowerShell Command Prompt Operating System Components System Libraries Software libraries and modules that provide functions APIs and services for application development and system programming Drivers Software components that interface with hardware devices manage device operations and provide communication between hardware and the OS Operating System Components Utilities System utilities and tools for system administration troubleshooting performance monitoring and system configuration e g Task Manager Disk Cleanup System Monitor Operating System Architecture Monolithic Kernel A single large kernel that handles all OS functions e g Linux kernel Microkernel Minimalistic kernel that delegates most OS functions to user space processes or modules e g MINIX QNX Operating System Architecture Hybrid Kernel Combines aspects of monolithic and microkernel architectures providing flexibility and performance optimizations e g Windows NT kernel macOS kernel Virtualization OS level virtualization e g Docker containers VirtualBox VMware and hypervisor based virtualization e g VMware ESXi Microsoft Hyper V for running multiple virtual machines VMs on a single physical machine Process Management Process Creation and Termination Creating executing suspending resuming and terminating processes managing process states e g running ready blocked Scheduling Algorithms CPU scheduling algorithms e g round robin priority based shortest job next for efficient process scheduling and resource allocation Process Management Interprocess Communication IPC Mechanisms for communication and data exchange between processes e g shared memory message passing pipes Memory Management Memory Allocation Allocating and deallocating memory for processes managing memory segments e g stack heap and preventing memory leaks and fragmentation Virtual Memory Using virtual memory techniques e g paging segmentation to manage memory efficiently and provide a larger address space than physical RAM Memory Management Memory Protection Enforcing memory protection mechanisms to prevent unauthorized access buffer overflows and memory corruption File System Management File Operations Creating opening reading writing closing deleting and modifying files and directories managing file permissions and attributes File System Types Different file system types e g FAT32 NTFS ext4 HFS with features such as journaling file compression encryption and symbolic links File System Management File System Integrity Ensuring file system integrity consistency and recovery mechanisms in case of file system errors or crashes Device Management Device Drivers Writing and managing device drivers for hardware devices e g graphics cards network adapters storage devices to enable communication with the OS Plug and Play PnP Automatic detection installation and configuration of hardware devices and drivers without manual intervention Device Management Interrupt Handling Managing hardware interrupts handling interrupt requests IRQs and prioritizing interrupt handling for critical devices Security and Access Control User Authentication Authenticating users through login credentials e g username password biometrics authentication protocols e g Kerberos LDAP and security tokens Access Control Implementing access control lists ACLs permissions roles and privilege levels to restrict access to system resources based on user permissions Security and Access Control Encryption Encrypting data at rest e g file encryption disk encryption and data in transit e g SSL TLS encryption to protect sensitive information Network Services and Communication Network Protocols Supporting network protocols e g TCP IP UDP HTTP FTP for communication between devices networks and Internet services Network Services and Communication Network Configuration Configuring network settings IP addressing routing tables DNS resolution DHCP server and network interfaces Network Services and Communication Network Services Providing network services such as file sharing e g SMB CIFS NFS printing services e g LPD IPP remote access e g SSH RDP and network monitoring Operating systems are fundamental to computer systems