Explain the difference between process and thread in an operating system and their interrelation.

A process is an instance of a running program that has its own address space, system resources (files, network connections, etc.), and thread(s) of execution. A thread is a unit of execution within a process that shares memory and resources with other threads of the same process but has its own stack and registers.

Main differences:

• Processes are isolated from each other, while threads within a process share memory.
• Creating a process is more resource-intensive than creating a thread.
• Threads allow for parallel execution of tasks within a single process.

Relationship: a process can contain one or more threads. Threads within a process share data, which facilitates information exchange but requires synchronization to prevent conflicts.