Operating System: Definitions and explanations page 2 PDF Download

Learn operating system definitions and explanations, OS course terminologies (Page 2) for computer science degree programs.


  1. What is Kernel Mode?
    There are two main modes i.e. kernel mode and user mode. in kernel mode, the code ...
  2. What is Kernel?
    A kernel is the central part of an operating system. the task of a kernel is ...
  3. What is Last In First Out (LIFO)?
    The acronym for last in first out is lifo. it is a method of processing data ...
  4. What is Lightweight Process?
    A lightweight process is a means of achieving multitasking. the threads created by users are implemented ...
  5. What is Livelock?
    Livelock is similar to deadlock, the difference is that the states of the processes involved in ...
  6. What is Locality of Reference?
    Locality of reference also called principle of locality, is the tendency of a processor to access ...
  7. What is Logical Address?
    Logical address is also known as virtual address. it is an address generated by the cpu ...
  8. What is Logical Record?
    A logical record is often structured and may be stored in numbers of full or partial ...
  9. What is Macrokernel?
    A very rare term often used to define kernel in a bigger picture. macrokernel is a ...
  10. What is Mailbox?
    A mailbox is a data buffer that can store a fixed number of messages and drafts ...
  11. What is Main Memory?
    Main memory is the physical memory that is the internal computer memory. the term main is ...
  12. What is Malicious Software?
    Malicious software also called malware (mal from malicious and ware from software) is any software program ...
  13. What is Memory Cycle Time?
    Memory cycle time is the time between the start of one random access memory (ram) access ...
  14. What is Memory Partitioning?
    Memory partitioning is done in two ways i.e. fixed partitioning and variable partitioning. in fixed partitioning, ...
  15. What is Message?
    A message is a unit of information that is sent to the user or the system ...
  16. What is Microkernel?
    A microkernel is the smallest amount of software that can provide enough information of the mechanisms ...
  17. What is Mode Switch?
    Mode property is generally associated with a process. so, a mode switch is switching of a ...
  18. What is Monitor?
    A monitor is a synchronization construct that allows threads to have both mutual exclusion and the ...
  19. What is Monolithic Kernel?
    Monolithic kernel is an operating system architecture where the entire operating system is working in kernel ...
  20. What is Multilevel Security?
    Multilevel security is the application of a computer system to process information with incompatible classifications, permit ...
  21. What is Multiprocessing?
    Multiprocessing is a computer system's ability to support more than one process at the same time. ...
  22. What is Multiprocessor?
    Multiprocessor is a type of processor that constitutes of two or more central processing units (cpus) ...
  23. What is Multiprogramming Level?
    Multiprogramming level is the number of processes placed in the main memory that are being executed ...
  24. What is Multiprogramming?
    Multiprogramming is a form of parallel processing in which several programs are run at the same ...
  25. What is Multitasking?
    Multitasking is allowing a user to perform more than one tasks at one time. the operating ...
  26. What is Mutex?
    Mutex (mut from mutual and ex from exclusion) is a mutual exclusion object which allows multiple ...
  27. What is Mutual Exclusion?
    Mutual exclusion is a program object that prevents simultaneous access to a shared resource. the concept ...
  28. What is Nonprivileged State?
    Nonproviliged state is an execution context that does not allow the system to execute any sensitive ...
  29. What is Nonuniform Memory Access Multiprocessor?
    Numa or nonuniform memory access is a method of configuring a cluster of microprocessor in a ...
  30. What is Object Request Broker?
    Object request broker is a middleware which allows program to be made from one computer to ...
  31. What is Operating System (OS)?
    Operating system is a low-level software that supports a computer's basic function, such as scheduling tasks ...
  32. What is Page Fault?
    Page fault occurs when a program attempts to access a block of memory that is not ...
  33. What is Page Frame?
    A page frame is the smallest fixed-length contagious block of physical memory into which pages are ...
  34. What is Page?
    A memory management scheme by which computer stores and retrieves data from secondary storage, such as ...
  35. What is Paging?
    Paging is a method of writing data ton and reading from, secondary storage for use in ...
  36. What is Physical Address?
    A physical address is a memory address that is represented in the form of a binary ...
  37. What is Pipe?
    A pipe is a technique for passing information from one program process to another. basically, a ...
  38. What is Preemption?
    Preemption is the act of temporarily interrupting a task being executed by a computer system, without ...
  39. What is Prepaging?
    Prepaging is a technique in which the operating system preloads the pages of a process's working ...
  40. What is Priority Inversion?
    Priority inversion is a scenario in scheduling in which a high priority task is indirectly preempted ...
  41. What is Privileged Instruction?
    A privileged instruction is an instruction that can be executed only by the operating system in ...
  42. What is Process Control Block (PCB)?
    Process control block also called task controlling block, task struct or switchframe, is a data structure ...
  43. What is Process Image?
    A process image is an image of a process taken when the memory is allocated to ...
  44. What is Process Migration?
    Process migration refers to the mobility of executing processes in a distributed computing environment. it indicates ...
  45. What is Process Spawning?
    Process spawning is a function that loads and executes a new child process. the current process ...
  46. What is Process State?
    Process state is the information provided to the operating system in order for it to manage ...
  47. What is Process Switch?
    A process switch is the shifting of operating system scheduler from one running program to another. ...
  48. What is Process?
    Process is basically a program in execution. it is the instance of a computer program that ...
  49. What is Processor?
    A processor is an integrated electronic circuit that performs the calculations that run a computer. a ...
  50. What is Program Counter?
    A program counter is a register in a computer processor that contains the location of the ...
  51. What is Program Status Word?
    The program status word (psw) is a collection of data which is 64 bits long. it ...
  52. What is Programmed IO?
    Programmed io is a way of moving data between devices in a computer in which all ...
  53. What is Race Condition?
    A race condition is an undesirable situation that occurs when a device or system attempts to ...
  54. What is Real Address?
    A real address, more commonly known as the physical address, is a memory address that is ...
  55. What is Real time System?
    A real-time system means that the system is subjected to real time. the response should be ...
  56. What is Record?
    A record, also called compound data, struct or a structure, is a basic data structure. a ...
  57. What is Reentrant Procedure?
    A reentrant procedure is one in which a single copy of the program can be shared ...
  58. What is Registers?
    A register is one of the small set of data holding place that are part of ...
  59. What is Relative Address?
    Relative address is a memory address that represents some distance from a starting point or the ...
  60. What is Remote Procedure Call (RPC)?
    Remote procedure call is a protocol that one program can use to request a service from ...