•  A process is a running programme, or an active programme. A thread is a small, self-contained process that can be handled by a scheduler.
• Time to switch contexts-Because processes are more complex, context switching takes longer. Because threads are lighter than processes, context switching takes less time.
• Sharing Memories-Processes are completely self-contained and do not exchange memory. A thread's peers may share some memory with it.
• Communication-It takes longer to communicate between processes than it does between threads. Thread communication takes less time than communication between processes.
• Blocked-If a process is blocked, the rest of the processes can continue to run. When a user level thread is blocked, it causes all of its peer threads to be blocked as well.
• Consumption of Resources-Threads use fewer resources than processes. 

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