OS

/ˌɪnˌpʊt ˌaʊtˈpuː mɛməri ˈmænɪdʒmənt ˈjuːnɪt/

noun — "translates and protects device memory access."

/ˈpɛɪdʒd ˈmɛməri ˈmænɪdʒmənt ˈjuːnɪt/

noun — "hardware that translates virtual pages into physical memory."

PMMU, short for Paged Memory Management Unit, is a hardware component responsible for implementing paged virtual memory by translating virtual addresses used by software into physical memory addresses used by the hardware. It sits between the CPU and main memory, enforcing memory isolation, access control, and address translation on every memory reference made by a running program.

/reɪs kənˈdɪʃən/

noun — "outcome depends on timing, not logic."

/ˌsɪŋkrənaɪˈzeɪʃən/

noun — "coordination of concurrent execution."

Synchronization is the set of techniques used in computing to coordinate the execution of concurrent threads or processes so they can safely share resources, exchange data, and maintain correct ordering of operations. Its primary purpose is to prevent race conditions, ensure consistency, and impose well-defined execution relationships in systems where multiple units of execution operate simultaneously.

/ˈmjuːtɛks/

noun — "locks a resource to one thread at a time."

Mutex, short for mutual exclusion, is a synchronization primitive used in multithreaded or multiprocess systems to control access to shared resources. It ensures that only one thread or process can access a critical section or resource at a time, preventing race conditions, data corruption, or inconsistent state. When a thread locks a mutex, other threads attempting to acquire the same mutex are blocked until it is released.

/ˈskɛdʒʊlər/

noun — "decides which task runs when."

/θrɛd/

noun — "smallest unit of execution within a process."

Thread is the basic unit of execution within a process, representing a single sequential flow of control that shares the process’s resources, such as memory, file descriptors, and global variables, while maintaining its own execution state, including program counter, registers, and stack. Threads allow a process to perform multiple operations concurrently within the same address space, enabling efficient utilization of CPU cores and responsiveness in multitasking applications.

/ˈproʊsɛs/

noun — "running instance of a program."

Process is an executing instance of a program along with its associated resources and state information managed by an operating system. It represents the fundamental unit of work in modern computing, providing an isolated environment in which instructions are executed, memory is allocated, and input/output operations are coordinated. A single program can have multiple concurrent processes, each maintaining its own independent state.

/ˈvɜːrtʃuəl ˈmɛməri/

noun — "memory abstraction larger than physical RAM."

Virtual Memory is a memory management technique that allows a computer system to present each process with the illusion of a large, contiguous address space, regardless of the actual amount of physical memory installed. It decouples a program’s view of memory from the hardware reality, enabling systems to run applications whose memory requirements exceed available RAM while maintaining isolation, protection, and efficiency.

/ˈpeɪdʒ rɪˈpleɪsmənt/

noun — "choosing which memory page to evict."

Page Replacement is the mechanism used by an operating system to decide which memory page should be removed from physical memory when space is needed to load a new page. It is a core component of virtual memory systems, enabling programs to operate as if they have access to more memory than is physically available by transparently moving data between fast main memory and slower secondary storage.