Modern Operating Systems Flashcards
What is the historical significance of operating systems?
Operating systems have existed almost as long as computers themselves and originally encapsulated recurring interaction tasks through system software by abstracting hardware.
What are some fundamental concepts introduced by operating systems?
Processes,memory management,and file systems.
Do the core roles of modern operating systems change over time?
No, the core roles of operating systems like Microsoft Windows, Linux, and macOS do not change.
What are the main differences among various operating systems?
Differences lie in the system’s structure,individual characteristics,and application areas.
What is Windows and who developed it?
Windows is a family of operating systems developed by Microsoft Corporation commonly seen running on personal computers (PCs).
What older operating system is Windows rooted in?
Windows is heavily rooted in MS-DOS (Microsoft Disk Operating System).
How did the first versions of Windows differentiate themselves from Microsoft DOS?
The first versions of Windows were extensions of Microsoft Desk Operating System that introduced a graphical user interface.
How can the development of Windows be divided?
The development of Windows can be divided into three eras: Systems based on MS-DOS;Systems based on the New Technology (NT) kernel;Modern NT-based systems starting with Windows 8
What was the official operating system of the original IBM PC?
The official operating system of the original IBM PC was MS-DOS
What was a major limitation of MS-DOS?
MS-DOS was a simple,single-user operating system with no multitasking functionality.
What were the first versions of Windows based on and what did they require?
The first versions of Windows were based on MS-DOS and required MS-DOS to interface with hardware.
What is the NT kernel and how does it differ from MS-DOS?
The NT kernel is a completely new project independent of MS-DOS, offering better CPU capabilities, memory protection, and the NTFS file system.
What significant innovations did NT provide compared to MS-DOS?
Innovations included better memory protection and the introduction of the NTFS file system.
What significant change did Windows 8 introduce?
Windows 8 introduced a new interface called Modern UI,designed for a new generation of computing devices.
What was the user response to the Modern UI interface?
There was strong user resistance to the changes,leading to the reinstatement of familiar concepts alongside the Modern UI features.
What are the two main functions of the central layers in privileged kernel mode?
They handle interruption and hardware-related CPU management and provide services for process/thread management,virtual memory management,and input/output management.
What is the Hardware Abstraction Layer (HAL)?
The HAL offers abstract machine oriented interfaces to the interrupt controller;memory management unit (MMU);and device controllers.
What is the Win32 API?
The Win32 API is a programming interface that provides standardized access to a comprehensive system library and abstracts system calls in the Windows kernel.
What was the major innovation of Windows NT regarding file systems?
The introduction of the New Technology File System (NTFS) as the default file system across all modern versions of Windows.
What is a significant limitation of the FAT file system?
The FAT32 variant has a file size limitation of 4GB;which is insufficient for storing larger files like uncompressed DVD images.
What advantages does NTFS offer over FAT?
NTFS solves the file size limitation issue and is a journaling file system;ensuring data structures are always consistent;which protects against data corruption during power outages or crashes.
Are Unix and Linux synonymous?
No..although Unix and Linux are often used synonymously in common speech due to their similarities;they have different code bases and development histories.
What term is used to refer to both Unix and Linux operating systems?
Both Unix and Linux operating systems are often referred to as “Unix-like.”
When and where did Unix development begin?
Unix development began in 1969 at the AT&T-founded Bell Telephone Laboratories.
Who were the pioneers involved in the development of Unix?
Ken Thompson and Dennis Ritchie were key figures in the development of Unix.
What programming language was developed for implementing Unix?
The C programming language was developed by Dennis Ritchie for implementing Unix.
What was the status of Unix in terms of openness until 1980?
Unix was a completely open-source operating system until 1980.
What are some common early and modern derivatives of Unix?
Common derivatives include Berkeley Software Distribution (BSD);Unix System V;SunOS/Solaris;FreeBSD;OpenBSD;NetBSD;and macOS.
What operating system did Andrew S. Tanenbaum develop in 1987?
Andrew S. Tanenbaum developed the open-source MINIX teaching operating system in 1987.
Who developed the Linux kernel and when was it released?
Linus Torvalds developed the Linux kernel and released it in 1991.
Under what license was Linux released and what is its significance?
Linux was released under the GNU General Public License, which offers developers protection against commercial projects that could harm the open-source spirit.
What role does Linus Torvalds play in the development of Linux?
Linus Torvalds has the final say on the development of Linux;overseeing contributions from various programmers (maintainers) in the open-source community.
How are Unix-like operating systems structured?
Unix-like operating systems are structured based on typical software layers;which can have standardized interfaces;allowing for the easy replacement of one layer with another.
What are two popular desktop environments used in Linux-based systems?
Two popular desktop environments are GNOME and KDE.
What is POSIX?
POSIX (Portable Operating System Interface) is a standard for Unix-like operating systems that defines a programming interface for system calls;including the names and parameters in C.
What does POSIX allow in terms of program execution?
POSIX allows POSIX-compatible C programs and shell scripts to be executed portably across many Unix-like operating systems without modification;as long as the operating systems are POSIX-compliant.
What does the “everything is a file” paradigm refer to in Unix-like systems?
The “everything is a file” paradigm refers to the concept that all hardware resources in a Unix/Linux system are presented to users as files.
What is the significance of the directory tree in Unix-like operating systems?
Unix-like systems have a single directory tree that contains both normal files and special files (like device files);which can be accessed in the same way as regular files.
How are storage devices accessed in Unix-like systems?
Storage devices are accessed by being mounted into the global directory tree
What command can be used to mount storage devices in Unix-like systems?
The mount command can be used to mount storage devices.
What are some well-known file systems used in Linux?
Common file systems for Linux include the Extended Filesystem (ext2/ext3);and in macOS (a Unix derivative);the Hierarchical File System Plus (HFS+) and Apple File System (APFS) are used.
What file system is commonly used for memory sticks and portable devices?
The FAT32 file system is commonly used for memory sticks and portable devices due to its support across various operating systems.
What are mobile operating systems designed for?
Mobile operating systems are designed for use on mobile devices;such as smartphones.
Are mobile operating systems special developments or derived from existing kernels?
They are usually derived from generic kernels that are also used in desktop and server systems.
What modifications are made to generic kernels for mobile use?
The kernels are streamlined for improved memory and energy consumption,special layers,drivers,and modules are added for mobile-specific features.
What kernel is Android based on?
Android is based on the Linux kernel.
What is the major difference between Android and other Linux distributions?
The major difference lies in the layers above the kernel,which are specific to Android and largely written in Java or C++.
What runtime environment does Android use for its Java-based code?
Android uses the Android Runtime (ART) for executing its Java-based code.
How do Android apps access hardware resources?
Android apps access hardware resources via system libraries that encapsulate the actual system calls in the kernel.
What framework makes system functions available to Android applications?
The Android Application Framework makes system functions available to applications.
Where can Android apps be downloaded and installed from?
Android apps can be downloaded and installed from Google Play,which is Google’s marketplace.
What is the containment model for Android apps?
Each app runs in its own virtual machine and is encapsulated in its own operating system process,belonging to its own (virtual) user.
How does Android manage access permissions for apps?
Android employs a granular approach to managing access permissions concerning private data,system functions,and special hardware resources.
How are processes for running Android apps initiated?
Processes can be initiated by the user,the system,or other applications.
What is an Android activity?
An Android activity represents a single user interface screen for an app that allows user interaction.
How can the starting activity of a mobile app vary?
The starting activity can vary based on the usage scenario,for instance,it may present different dialogs when launched from a navigation app compared to the start screen.
What feature of Android allows for flexible user interactions with apps?
The ability to combine different activities from different apps based on the context of the usage scenario makes the system flexible.
What are crucial elements of Android’s security concept?
Android’s security concept includes granular access permissions for private data,system functions,and hardware resources,protecting user privacy and device integrity.
What are the basic concepts shared by modern operating systems across all platforms?
Modern operating systems share basic concepts such as processes,virtual memory,and file systems.
How does the role of operating systems like Windows,Linux and Unix remain consistent?
The role of these operating systems remains the same across different platforms (servers or smartphones),only their structure and characteristics may vary.
What does the similarity in operating system concepts imply for their functionality?
It implies that the fundamental functionality and roles of operating systems are consistent,allowing for common usage patterns and behaviors.
What unique adaptations are made to operating systems for mobile devices?
Mobile operating systems undergo special configurations,streamlining and/or extensions to make generic kernels more suitable for mobile use.
Why is it important for operating systems to be adapted for mobile use?
Adaptations are important for improving performance in terms of memory and energy consumption,and for enabling mobile-specific features.
How do the adaptations for mobile operating systems differ from traditional operating systems?
Mobile operating systems prioritize efficiency and responsiveness in a limited resource environment,while traditional operating systems may focus on broader functionality for powerful hardware.
What do abstraction concepts in modern operating systems enable?
Abstraction concepts allow operating systems to manage hardware resources more efficiently and provide a consistent interface for applications.
Can the concepts of processes and virtual memory be found in all operating systems?
Yes..these concepts are foundational and present in all current operating systems and their families.
In what way do mobile operating systems illustrate the need for specific adaptations?
Mobile operating systems demonstrate the need for specific adaptations by highlighting how generic kernels can be modified to suit the unique constraints and requirements of mobile devices.
