Open a QQ, open a process; open Thunder, open a process.
In this process of QQ, a thread is opened for text transmission, another thread is opened for voice transmission, and another thread is opened for pop-up dialog boxes.
So running a certain software is equivalent to opening a process. In the process of running this software (in this process), multiple jobs support the completion of the running of QQ, then each of these "multiple jobs" has a thread.
So a process manages multiple threads.