A Linux command is a program or utility that runs on the command line. A command line is an interface that accepts lines of text and processes them into instructions for your computer.
Any graphical user interface (GUI) is just an abstraction of command-line programs. For example, when you close a window by clicking on the “X,” there’s a command running behind that action.
A flag is a way we can pass options to the command you run. Most Linux commands have a help page that we can call with the flag -h. Most of the time, flags are optional.
An argument or parameter is the input we give to a command so it can run properly. In most cases, the argument is a file path, but it can be anything you type in the terminal.
You can invoke flags using hyphens (-) and double hyphens (–), while argument execution depends on the order in which you pass them to the function.