Tags: Interview , Process , Thread

Image clarifies the difference between Process and Thread. However lets discuss it point by point.

Process
A process has a self-contained execution environment. An instance of program called Process.

• Each Process has its own address space.
• Process have to use Inter Process Communication (IPC) resource like pipes and sockets to communicate with other process.
• New processes require duplication of the parent process.
• Processes have considerable overhead.
• Process have their own copy of data segment of the parent process.
• Process have control over its child processes.
• Any change in the parent process does not affect child processes.
• Process is controlled by the operating system.
• Processes are independent.

Thread
Threads are sometimes called lightweight processes. It runs within the Process.

• Thread(s) shares the address space of Process that created it.
• Threads can directly communicate with other Threads of its process.
• New threads can be created easily.
• Threads have almost no overhead.
• Threads have direct access to data segment of its Process.
• Threads have considerable control over threads of the same process.
• Any change in main thread (cancellation, priority change, etc...) may affect the behavior of the other threads of the process.
• Threads are controlled by programmer in a program.
• Threads are dependent.

Tags: Interview , Process , Thread