True or False?

Operating systems protect the memory allocated to each process from access by other processes, but if virtual memory is used by a process, all of that processes memory may be read or written by every other process using virtual memory.

The bytes stored as files within a file system may be mapped into a virtual address space. The bytes of memory mapped files may be accessed using virtual addresses just like bytes that are not from a memory mapped file.

Most Unix/Linux "Commands" are actually programs. The main purpose of a shell is to start and interact with other programs. A shell is a program for interacting with other programs. Unix/Linux systems come with many different command line shells. Modern Windows computers come with two different command line shells, cmd and Powershell, and at least one graphical shell.

Unix/Linux and WIndows shells are programming language interpreters. One reason so many different shells exist is that each shell interprets a slightly different programming language. Users select a preferred shell based largely on personal preferences about programming languages. Almost every command line shell treats everything you type as the text of a program. It doesn't matter that most of the programs you write in a shell are only one line long. That's part of the power of shells.

By making a process's Text/Code segment readable and executable but not writable, an operating system can protect the process from many types of malware because the malware must write malicious machine instructions into memory and then cause the malicious machine instructions to execute.