Entitlements are commonly used in Linux system protection.

The degree of multiprogramming refers to the number of processes in memory.

An orphan process is a process that has been terminated but whose parent has not yet called wait().

Linux distinguishes between processes and threads.

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

Microsoft Windows uses the one-to-one thread mapping model.

The heap section is the section of process memory that is dynamically allocated during process run time.

A parallel system can perform more than one task simultaneously.

For each program, the text and data sections can shrink and grow dynamically during program execution.

It is possible to have concurrency without parallelism.