1Operating System (OS) acts as an intermediary program between a computer user and the hardware
It serves as a bridge between the user and the computer hardware, managing hardware and providing an easier interface
2What does the OS shield programmers from?
Hardware complexity
3What is another name for the one program running at all times in a computer system?
Kernel
4What facilitates communication between the OS and application programs?
System calls or extended instructions
5What is the first program that runs when you boot up your computer?
Bootstrap program
6What does the bootstrap program initialize?
All aspects of the system, including CPU, memory, and device controllers
7What does the bootstrap program do after initialization?
Locates the operating system
8What is the final step the bootstrap program performs?
Loads OS kernel into memory
9What are system programs responsible for?
Managing the operations of the computer
10What do multitasking systems allow?
Running more than one process at a time
11What do single-user systems support?
One user at a time
12What are the main components of a computer system?
Users, application programs, operating systems, and hardware
13How does the OS act as a system manager?
By controlling hardware and software and serving as an interface between user and system
14What is the purpose of program execution service in an OS?
Loads, runs, and terminates programs
15What does input-output operations service control?
Input-output devices
16What does file system manipulation allow?
Reading, writing, deletion, and creation of files
17What does the communication service manage?
Shared memory or message passing between processes
18What is the function of error detection in an OS?
Corrects errors to ensure a consistent system state
19What does resource allocation in an OS involve?
Using CPU scheduling for memory, I/O devices, and file storage to optimize CPU use
20What does accounting service in an OS do?
Tracks user resource usage and provides statistics for performance improvement
21What does protection service ensure?
User, process, and data protection
22What are the layers of a computer system from top to bottom?
End user, application programs, utilities, operating system, hardware
23What mode does the OS run in to protect users from hardware tampering?
Kernel or supervisor mode
24What are the two main classifications of operating systems?
Distributed Operating Systems and Concurrent Operating Systems
25What is the focus of distributed operating systems?
Distributing tasks across multiple computers
26What key characteristic makes a distributed OS appear as a single system?
Transparency
27What resources are shared in a distributed OS?
Files, printers, and storage across the network
28What is an advantage of distributed operating systems?
Each processor has a dedicated function, useful for data centres
29What is the focus of concurrent operating systems?
Managing multiple tasks on a single computer
30How do concurrent OS handle multiple tasks?
By interleaving execution of tasks
31What are key characteristics of concurrent OS?
Single computer, multitasking, process management, memory management
32What is an advantage of concurrent OS?
Minimizes communication overhead, faster response times, reduced latency
33Give examples of concurrent operating systems
Windows 11, macOS Ventura, Linux, Android
34What does a multitasking operating system allow?
Simultaneous execution of multiple programs using a single processor
35What does a multiprogramming OS allow?
More than one active user program in main memory simultaneously
36What defines a multiprocessing OS?
Having more than one independent processing unit
37What is a time-sharing operating system designed for?
Enabling multiple simultaneous users with shared memory, CPU, and resources
38What is the main feature of a real-time operating system (RTOS)?
Responds within a certain period of time for critical applications
39What is a batch operating system?
Executes jobs one at a time, collected in batches without interruption