Introduction to the Linux Command Line Interface

In this lesson, you will be introduced to the Linux Command Line Interface (CLI), an essential tool for interacting with Unix/Linux-based operating systems. You will learn what the CLI is, its advantages, and how to get help using the command line.

What is the Command Line Interface (CLI)?

The Command Line Interface, often referred to as the CLI or terminal, is a text-based interface for interacting with a computer's operating system. It allows users to issue commands to the computer by typing text-based instructions rather than using a graphical user interface (GUI). The CLI is a powerful and efficient way to control and manage a Unix/Linux system.

Advantages of Using the CLI

Why would you want to use the CLI when you have a graphical desktop environment available? Here are some advantages:

1. Efficiency: The CLI is often faster for experienced users to perform tasks.
2. Scripting and Automation: You can create scripts to automate repetitive tasks.
3. Resource Efficiency: The CLI consumes fewer system resources than a GUI.
4. Remote Access: You can access and manage remote servers over a network.

Commandline

When you first enter the shell session you will see output like the following:

Let's break it down:

• **paulh**: This is the username of the current user who is logged into the system.
• **@**: This symbol separates the username from the hostname.
• **ubuntu-server**: This is the hostname of the computer or server. In this example, the system is named "ubuntu-server."
• **~**: The tilde character represents the current user's home directory. In Unix/Linux systems, the tilde (~) is a shorthand notation for the home directory of the currently logged-in user. In this case, it indicates that the user "paulh" is in their home directory.
• **$**: The dollar sign ($) is the command prompt symbol. It signifies that the command line is…