Difference between processes and threads

The major difference between threads and processes is :

1. Threads share the address space of the process that created it; processes have their own address.
2. Threads have direct access to the data segment of its process; processes have their own copy of the data segment of the parent process.
3. Threads can directly communicate with other threads of its process; processes must use inter process communication to communicate with sibling processes.
4. Threads have almost no overhead; processes have considerable overhead.

5. New threads are easily created; new processes require duplication of the parent process.
6. Threads can exercise considerable control over threads of the same process; processes can only exercise control over child processes.
7. Changes to the main thread (cancellation, priority change, etc.) may affect the behavior of the other threads of the process; changes to the parent process do not affect child processes.