Protection is not one of the major categories of system calls.

It is possible to have concurrency without parallelism.

A process that has terminated but whose parent has not yet called wait() is known as an init process.

The first-in, first-out (FIFO) algorithm will replace the page that will not be used for the longest period.

As processes enter the system, they are put into a wait queue.

On a mobile device, the foreground application is the app that does not appear on display.

A process control block (PCB) is also called a task control block.

A "blocking send()" and "blocking receive()" are known as "blocked messages."

The program counter of a process contains temporary data such as function parameters, return addresses, and local variables.