Summary
The number 7754 is a process ID that the operating system assigned to it. On a single core machine, the processes execute concurrently. The reason behind this behaviour is that the OS has scheduling algorithms that decide when to run each process. This happens back and forth until all the tasks have been finished.
In Node.js, each process has its own thread. This means that each process is able to run in a single thread. It is possible to run multiple processes in the same process. This is known as a ‘multi-core’ process. It means that the process can run in multiple threads.
