Glossary

Plain, one-line explanations of Linux terms you will run into while learning.

DAC
An access control model where the file owner decides who else gets access (Discretionary Access Control).
directory
A container that organizes files. Same idea as a "folder" on Windows or macOS.
environment variable
A named value that the shell or a program can look up while running.
kernel
The core program of an OS. It bridges hardware and software.
login shell
The first shell started right after a user logs in.
MAC
A system-wide access control model enforced by fixed rules (Mandatory Access Control).
package manager
A tool that installs and updates software for you in one place.
path
A string that describes the location of a file or directory.
permission
The read / write / execute access rules set on a file or directory.
prompt
A symbol (like $ or #) shown when the shell is waiting for your input.
quote
Wrapping a string in quote marks (' or ") so it is treated as one single value, e.g. one with spaces in it.
root
The special administrator account allowed to do anything on the system.
shell
An interactive program that reads the commands you type and runs them.