Difference between Process and Thread
Last Updated :
02 Jan, 2026
Process and threads are the basic components in OS. Process is a program under execution whereas a thread is part of process. Threads allows a program to perform multiple tasks simultaneously, like downloading a file while you browse a website or running animations while processing user input. A process can consists of multiple threads. In this article we will explore difference between process and thread in detail.
Process Processes are basically the programs that are dispatched from the ready state and are scheduled in the CPU for execution. PCB ( Process Control Block ) holds the context of process. A process can create other processes which are known as Child Processes. The process takes more time to terminate, and it is isolated means it does not share the memory with any other process. The process can have the following states new, ready, running, waiting, terminated and suspended.
Read more about Introduction to Process Management.
Process Advantages of Processes
Work independently in separate memory, improving security. Efficient allocation of CPU and memory resources. Can be prioritized for better task management. Disadvantages of Processes
Context switching can reduce system speed. Poor resource handling may cause deadlocks. Too many processes increase memory usage and management overhead. Thread Threads are often called "lightweight processes" because they share some features of processes but are smaller and faster. Each thread is always part of one specific process. A thread has three states: Running, Ready and Blocked.
A thread takes less time to terminate as compared to the process but unlike the process, threads do not isolate.
Examples:
When you use a mobile banking app, multiple threads work together to keep it smooth. One thread loads your latest balance, another handles your touch inputs, and another loads images or icons. Because these threads run at the same time, you can scroll and tap normally while the app continues loading data in the background. Process vs Thread Advantages of Threads
Improve performance by running tasks in parallel, especially with I/O work. Faster to create and destroy than processes. Allow applications to handle multiple tasks at the same time. Disadvantages of Threads
Share memory, so errors in one thread can affect others. Shared resources may cause conflicts and unexpected behavior. Too many threads can reduce performance and exhaust memory. Process Vs Thread The table below represents the difference between process and thread.
Process Thread Program in execution Part of a process Takes more time to create & terminate Takes less time to create & terminate Context switching is slow Context switching is fast Heavyweight Lightweight Has its own memory space Shares memory with other threads Less efficient communication More efficient communication Blocking one process doesn’t affect others Blocking a user-level thread may block all Uses system calls Created using APIs (may not need OS call) Has its own PCB, stack, address space Shares PCB & address space, has own TCB & stack Does not share data Shares data with other threads
OS - Thread vs Process
Process vs Threads in Operating System
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