What is the difference between lightweight process and thread?

Question

I found an answer to the question here. But I don\'t understand some ideas in the answer. For instance, lightweight process is said to share its logical address space with other

Answer 1

Threads run within processes.

Each process may contain one or more threads.

If kernel doesn't know anything about the threads running in the process, we have threads running on user space and thus no multiprocessing capabilities are available.

On the other hand, we can have threads running on the kernel space; this means that each process runs on a different CPU. This enables us multiprocessing, but as you may assume it is more expensive in terms of operating system resources.

Finally, there is a solution that lies somewhere in the middle; we group threads together into LWP. Each group runs on different CPU, but the threads in the group cannot be multi processed. That's because kernel in this version knows only about the groups (which are multiprocessed) but nothing about the threads that they contain. Hope it is clear enough.