Threads vs Processes
A process is an independent program with its own memory space, file handles, and operating system resources. A thread is a unit of execution that lives inside a process.
Key distinctions:
- Memory A process owns a private address space. Threads inside one process share that same heap and global data.
- Isolation Processes are isolated, so a crash in one rarely harms another. Threads share fate because a bad pointer can corrupt the whole process.
- Communication Threads talk through shared memory, which is fast but needs synchronization. Processes use inter process communication such as pipes or sockets.
- Cost Creating a thread is cheap. Creating a process is heavier because the operating system must allocate a new address space.
Because threads share memory, they enable fast data exchange but introduce race conditions when two threads touch the same variable without coordination. Processes trade speed for safety.
Choose threads when you need lightweight parallelism within shared data. Choose processes when isolation and fault tolerance matter more than raw speed.
Key idea
Threads share memory inside one process for speed; processes stay isolated for safety at a higher cost.